Conductive sheet and touch panel

ABSTRACT

A conductive component includes a first electrode pattern made of metal thin wires, and includes a plurality of first conductive patterns that extend in a first direction alternating with first non-conductive patterns. Each first conductive pattern includes break parts in portions other than intersection parts of the thin metal wires. The conductive component further includes a second electrode pattern made of thin metal wires, and includes a plurality of second conductive patterns that extend in a second direction orthogonal to the first direction and alternating with second non-conductive patterns. Each second conductive pattern includes break parts in portions other than intersection parts of thin metal wires.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. application Ser. No.16/538,369, filed Aug. 12, 2019, which is a Continuation of U.S.application Ser. No. 16/371,673, filed Apr. 1, 2019, now U.S. Pat. No.10,433,419, which is a Continuation of U.S. application Ser. No.16/124,495 filed Sep. 7, 2018, now U.S. Pat. No. 10,299,377, which is aContinuation of U.S. application Ser. No. 15/845,288 filed Dec. 18,2017, now U.S. Pat. No. 10,111,326, which is a Continuation of U.S.application Ser. No. 14/310,770 filed Jun. 20, 2014, now U.S. Pat. No.9,877,385, which is a Continuation of PCT International Application No.PCT/JP2012/083222 filed on Dec. 21, 2012, which claims priorities under35 U.S.C § 119(a) to Japanese Patent Application No. 2011-281928 filedDec. 22, 2011, Japanese Patent Application No. 2012-113741 filed May 17,2012, and Japanese Patent Application No. 2012-182678 filed Aug. 21,2012. Each of the above applications is hereby expressly incorporated byreference, in its entirety, into the present application.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a conductive sheet and a touch panel.

Description of the Related Art

In recent years, touch panels are frequently used as input devices forportable terminals and computers. Such a touch panel is placed on asurface of a display, and performs an input operation by detecting aposition touched with a finger or the like. For example, a resistancefilm type and a capacitive type are known as a position detecting methodfor a touch panel.

For example, in a capacitive touch panel, indium tin oxide (ITO) is usedas a material of a transparent electrode pattern, from the perspectiveof visibility. ITO, however, has a high wiring resistance and does nothave a sufficient transparency, and hence it is discussed that atransparent electrode pattern formed using metal thin wires is used fora touch panel.

Studies on transparent conductive films formed using metal thin wiresare continued as disclosed in, for example, U.S. Patent ApplicationPublication No. 2004/0229028 and Pamphlet of International PublicationNo. WO 2006/001461. If an electrode is formed by arranging a largenumber of grids made of metallic thin wires (metal thin wires), thesurface resistance is considered to be reduced. For example, JapanesePatent Application Laid-Open No. 5-224818. Pamphlet of InternationalPublication No. WO 1995/27334. U.S. Patent Application Publication No.2004/0239650. U.S. Pat. No. 7,202,859. Pamphlet of InternationalPublication No. WO 1997/18508 and Japanese Patent Application Laid-OpenNo. 2003-099185 are known as touch panels in which metal thin wires areused to form electrodes.

Japanese Patent Application Laid-Open No. 2010-277392 discloses a touchpanel including: a plurality of first detection electrodes that are madeof net-like conducive wires and are placed in parallel in one direction;and a plurality of second detection electrodes that are made of net-likeconductive wires and are placed in parallel in a direction orthogonal tothat of the first detection electrodes.

SUMMARY OF THE INVENTION

In the touch panel of Japanese Patent Application Laid-Open No.2010-277392, if the touch panel is touched with a finger, a change inelectrostatic capacitance that occurs in the electrodes is determined,whereby a position touched with the finger is detected. However, in atouch panel of U.S. Patent Application Publication No. 2004/0229028, inthe case where an upper electrode is made of a uniform conductive regionand does not have a nonconductive region, even if a finger or the likecomes into contact with the touch panel, lines of discharged electricforce are closed between the electrodes, and the detection performanceof the contact of finger may become lower in some cases.

The present inventors have examined various configurations of net-likeelectrodes. The present inventors find out that, in the case where breakparts are formed in a net-like electrode, the break parts stand outdepending on the positions of the break parts. For example, in the casewhere the break parts are respectively formed in intersection parts of aplurality of conductive wires that form the net-like electrode, anopening portion of each break part is observable as it is opened. Ifsuch opening portions (break parts) are arranged on a straight line, thebreak parts are recognized as a pattern, and hence the visibility may beunfavorably impaired.

The present indention, which has been made in view of such a problem,has an object to provide a conductive sheet and a touch panel thatinclude electrode patterns made of metal thin wires and have a highdetection accuracy of a contact position (touch position) on the touchpanel.

The present invention has another object to provide a conductive sheetand a capacitive touch panel that do not impair the visibility.

A conductive sheet according to one aspect of the present inventionincludes: a substrate having a first main surface and a second mainsurface; and a first electrode pattern placed on the first main surfaceof the substrate. The first electrode pattern is made of metal thinwires, and alternately includes: a plurality of first conductivepatterns that extend in a first direction; and a plurality of firstnonconductive patterns that are electrically separated from theplurality of first conductive patterns. Each of the first conductivepatterns includes, at least, inside thereof, a sub-nonconduction patternthat is electrically separated from the first conducive pattern. An areaA of each first conductive patterns and an area B of eachsub-nonconduction pattern satisfy a relation of 5%<B/(A+B)<97%.

Preferably, the area A of each first conductive pattern and the area Bof each sub-nonconduction pattern satisfy a relation of 10%≤B/(A+B)≤80%.

Preferably, the area A of each first conductive pattern and the area Bof each sub-nonconduction pattern satisfy a relation of 10%≤B/(A+B)≤60%.

Preferably, in the conductive sheet, each sub-nonconduction pattern hasa slit-like shape extending in the first direction, each firstconductive pattern includes a plurality of first conductive patternlines divided by each sub-nonconduction pattern, and an area A1 of eachfirst conductive pattern and an area B1 of each sub-nonconductionpattern satisfy a relation of 40%≤B1/(A1+B1)≤60%.

Preferably, a total width Wa of widths of the first conductive patternlines and a total width Wb of: a total width of widths of thesub-nonconduction patterns; and a width of the first nonconductivepattern satisfy relations of the following expressions (1) and (2).1.0 mm≤Wa≤5.0 mm  (1)1.5 mm≤Wb≤5.0 mm  (2)

Preferably, in the conductive sheet, the first conductive pattern hasX-shaped structures with cyclical intersections, and an area A2 of thefirst conductive pattern and an area B2 of the sub-nonconduction patternsatisfy a relation of 20%≤B2/(A2+B2)≤50%, and more preferably satisfy arelation of 30%≤B2/(A2+B2)≤50%.

Preferably, the conducive sheet further includes a second electrodepattern placed on the second main surface of the substrate. The secondelectrode pattern is made of metal thin wires, and includes a pluralityof second conductive patterns that extend in a second directionorthogonal to the first direction.

Preferably, in the conductive sheet, the plurality of first conductivepatterns are formed by grids having uniform shapes, and each of thegrids has one side having a length that is equal to or more than 250 μmand equal to or less than 900 μm.

Preferably, each of the metal thin wires that form the first electrodepattern and/or the metal thin wires that form the second electrodepattern has a wire width equal to or less than 30 μm.

Preferably, in the conductive sheet, a width of the first conductivepattern line and a width of the sub-nonconduction pattern aresubstantially equal to each other.

Preferably, in the conductive sheet, a width of the first conductivepattern line is smaller than a width of the sub-nonconduction pattern.

Preferably, in the conducive sheet, a width of the first conductivepattern line is larger than a width of the sub-nonconduction pattern.

Preferably, in the conductive sheet, the first electrode patternincludes a joining part that electrically connects the plurality offirst conductive pattern lines to each other.

Preferably, in the conductive sheet, a number of the first conductivepattern lines is equal to or less than ten.

Preferably, in the conductive sheet, the sub-nonconduction pattern issurrounded by a plurality of sides, and the sides are formed by linearlyarranging a plurality of grids that form the first conductive pattern,with sides of the grids being connected to each other.

Preferably, in the conductive sheet, each of the sub-nonconductionpattern is surrounded by a plurality of sides, and the sides are formedby linearly arranging, in multiple stages, a plurality of grids thatform the first conductive pattern, with sides of the grids beingconnected to each other.

Preferably, in the conductive sheet, the sub-nonconduction pattern issurrounded by a plurality of sides, some of the sides are formed bylinearly arranging a plurality of grids that form the first conductivepattern, with sides of the grids being connected to each other, and theother sides are formed by linearly arranging the plurality of grids withapex angles of the grids being connected to each other.

Preferably, in the conductive sheet, the plurality of sub-nonconductionpatterns defined by the sides formed by the plurality of grids arearranged along the first direction with apex angles of the grids beingconnected to each other.

Preferably, in the conductive sheet, adjacent ones of thesub-nonconduction patterns along the first direction have shapesdifferent from each other.

Preferably, in the conductive sheet, each of the plurality of grids thatform the sides for defining the sub-nonconduction patterns furtherincludes a protruding wire made of a metal thin wire.

Preferably, in the conductive sheet the first conductive patternincludes the sub-nonconduction patterns at predetermined intervals, tothereby have X-shaped structures in which the grids are not present atcyclical intersection parts.

Preferably, in the conductive sheet, adjacent ones of thesub-nonconduction patterns along the first direction have the same shapeeach other in the first conductive pattern, and the sub-nonconductionpatterns have shapes different between adjacent ones of the firstconductive patterns.

A touch panel, preferably a capacitive touch panel, and more preferablya projected capacitive touch panel according to another aspect of thepresent invention includes the conductive sheet of the presentinvention.

A conductive sheet according to another aspect of the present inventionincludes: a substrate having a first main surface and a second mainsurface; and a first electrode pattern placed on the first main surface.The first electrode pattern is formed by a plurality of grids made of aplurality of metal thin wires that intersect with each other, andalternately includes: a plurality of first conductive patterns thatextend in a first direction; and a plurality of first nonconductivepatterns that electrically separate the plurality of first conductivepatterns from each other. Each of the first nonconductive patternsincludes first break parts in portions other than intersection parts ofthe metal thin wires. The conductive sheet includes a second electrodepattern placed on the second main surface. The second electrode patternis formed by a plurality of grids made of a plurality of metal thinwires that intersect with each other, and alternately includes: aplurality of second conductive patterns that extend in a seconddirection orthogonal to the first direction; and a plurality of secondnonconductive patterns that electrically separate the plurality ofsecond conducive patterns from each other. Each of the secondnonconductive patterns includes second break parts in portions otherthan intersection parts of the metal thin wires. The first electrodepattern and the second electrode pattern are placed on the substratesuch that the plurality of first conductive patterns and the pluralityof second conductive patterns are orthogonal to each other in lop viewand that the grids of the first electrode pattern and the grids of thesecond electrode pattern form small grids in top view.

Another conductive sheet according to the present invention includes: afirst substrate having a first main surface and a second main surface;and a first electrode pattern placed on the first main surface of thefirst substrate. The first electrode pattern is formed by a plurality ofgrids made of a plurality of metal thin wires that intersect with eachother, and alternately includes, a plurality of first conducive patternsthat extend in a first direction; and a plurality of first nonconductivepatterns that electrically separate the plurality of first conductivepatterns from each other. Each of the first nonconductive patternsincludes first break parts in portions other than intersection parts ofthe metal thin wires. The conductive sheet includes: a second substratehaving a first main surface and a second main surface; and a secondelectrode pattern placed on the first main surface of the secondsubstrate. The second electrode pattern is formed by a plurality ofgrids made of a plurality of metal thin wires that intersect with eachother, and alternately includes: a plurality of second conductivepatterns that extend in a second direction orthogonal to the firstdirection; and a plurality of second nonconductive patterns thatelectrically separate the plurality of second conductive patterns fromeach other. Each of the second nonconductive patterns includes secondbreak parts in portions other than intersection parts of the metal thinwires. The first substrate and the second substrate are placed such thatthe plurality of first conductive patterns and the plurality of secondconductive patterns are orthogonal to each other in top view and thatthe grids of the first electrode pattern and the grids of the secondelectrode pattern form small grids in top view.

Preferably, in the conductive sheet according to the another aspect ofthe present invention, the first break parts are respectively locatednear centers between the intersection parts and the intersection partsof the metal thin wires of the first nonconductive patterns, and thesecond break parts are respectively located near centers between theintersection parts and the intersection parts of the metal thin wires ofthe second nonconductive patterns.

Preferably, in the conductive sheet according to the another aspect ofthe present invention, each of the first break parts and the secondbreak parts has a width that exceeds a wire width of each of the metalthin wires and is equal to or less than 50 μm.

Preferably, in the conductive sheet according to the another aspect ofthe present invention, the metal thin wires of the second conductivepatterns are located in the first break parts of the first nonconductivepatterns in top view, and the metal thin wires of the first conductivepatterns are located in the second break parts of the secondnonconductive patterns in lop view.

Preferably, in the conductive sheet according to the another aspect ofthe present invention, assuming that a width of each of the metal thinwires of the first conductive patterns and the metal thin wires of thesecond conductive patterns is a and that a width of each of the firstbreak parts of the first nonconductive patterns and the second breakparts of the second nonconductive patterns is b, a relational expressionof b−a≤30 μm is satisfied.

Preferably, in the conductive sheet according to the another aspect ofthe present invention, assuming that a width of each of the metal thinwires of the first conductive patterns and the metal thin wires of thesecond conductive patterns is a and that a width of each of the firstbreak parts of the first nonconductive patterns and the second breakparts of the second nonconductive patterns is b, a relational expressionof (b−a)/a≤6 μm is satisfied.

Preferably, in the conductive sheet according to the another aspect ofthe present invention, a positional misalignment between: a centralposition of each of the metal thin wires of the first conductivepatterns; and a central position of each of the second break parts ofthe second nonconductive patterns has a standard deviation equal to orless than 10 μm, and a positional misalignment between: a centralposition of each of the metal thin wires of the second conductivepatterns; and a central position of each of the first break parts of thefirst nonconductive patterns has a standard deviation equal to or lessthan 10 μm.

In the conductive sheet according to the another aspect of the presentinvention, the grids of the first electrode pattern and the grids of thesecond electrode pattern have a grid pitch of 250 μm to 900 pin, andpreferably have a grid pitch of 300 μm to 700 μm, and the small gridshave a grid pitch of 125 μm to 450 μm, and preferably have a grid pitchof 150 μm to 350 μm.

Preferably, in the conductive sheet according to the another aspect ofthe present mention, each of the metal thin wires that form the firstelectrode pattern and the metal thin wires that form the secondelectrode pattern has a wire width equal to or less than 30 μm.

Preferably, in the conductive sheet according to the another aspect ofthe present invention, each of the grids of the first electrode patternand the grids of the second electrode pattern has a rhomboid shape.

A capacitive touch panel according to the present invention includes anyone of the above-mentioned conductive sheets.

The conductive sheets according to the above-mentioned aspects and thecapacitive touch panel can suppress a decrease in visibility.

According to the present invention, it is possible to provide aconductive sheet and a touch panel that include electrode patterns madeof metal thin wires and have a high detection accuracy.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic plan view of a conductive sheet for a touch panel.

FIG. 2 is a schematic cross-sectional view of the conductive sheet.

FIG. 3 is an explanatory diagram for describing a behavior of the touchpanel including the conductive sheet of the present embodiment.

FIG. 4 is an explanatory diagram for describing a behavior of a touchpanel including a conventional conductive sheet.

FIG. 5 is a plan view illustrating an example of a first electrodepattern of a first embodiment.

FIG. 6 is a plan view illustrating an example of another first electrodepattern of the first embodiment.

FIG. 7 is a plan view illustrating an example of another first electrodepattern of the first embodiment.

FIG. 8 is a plan view illustrating an example of another first electrodepattern of the first embodiment.

FIG. 9 is a plan view illustrating an example of another first electrodepattern of the first embodiment.

FIG. 10 is a plan view illustrating an example of another firstelectrode pattern of the first embodiment.

FIG. 11 is a plan view illustrating an example of another firstelectrode pattern of the first embodiment.

FIG. 12 is a plan view illustrating an example of a first electrodepattern of a second embodiment.

FIG. 13 is a plan view illustrating an example of another firstelectrode pattern of the second embodiment.

FIG. 14 is a plan view illustrating an example of another firstelectrode pattern of the second embodiment.

FIG. 15 is a plan view illustrating an example of another firstelectrode pattern of the second embodiment.

FIG. 16 is a plan view illustrating an example of another firstelectrode pattern of the second embodiment.

FIG. 17 is a plan view illustrating an example of another firstelectrode pattern of the second embodiment.

FIG. 18 is a plan view illustrating an example of another firstelectrode pattern of the second embodiment.

FIG. 19 is a plan view illustrating an example of another firstelectrode pattern of the second embodiment.

FIG. 20 is a plan view illustrating an example of another firstelectrode pattern of the second embodiment.

FIG. 21 is a plan view illustrating an example of another firstelectrode pattern of the second embodiment.

FIG. 22 is a plan view illustrating an example of another firstelectrode pattern of the second embodiment.

FIG. 23 is a plan view illustrating an example of a second electrodepattern of the present embodiment.

FIG. 24 is a plan view illustrating an example of a conductive sheet fora touch panel in which the first electrode pattern and the secondelectrode pattern are combined with each other.

FIG. 25 is a plan view illustrating an example of another conductivesheet for a touch panel in which the first electrode pattern and thesecond electrode pattern are combined with each other FIG. 26 is a planview illustrating an example of the first electrode pattern of the firstembodiment, including dummy patterns.

FIG. 27 is a partial enlarged view of the dummy pattern.

FIG. 28 is a plan view illustrating an example of the first electrodepattern of the second embodiment, including dummy patterns.

FIG. 29 is a plan view illustrating an example of the second electrodepattern including a dummy pattern.

FIG. 30 is a partial enlarged view of the dummy pattern.

FIG. 31 is a plan view illustrating an example of another conductivesheet for a touch panel in which the first electrode pattern and thesecond electrode pattern are combined with each other.

FIG. 32 is a plan view illustrating an example of still anotherconductive sheet for a touch panel in which the first electrode patternand the second electrode pattern are combined with each other.

FIG. 33 is a schematic cross-sectional view of another conductive sheet.

FIG. 34 is an exploded perspective view illustrating, with partialomission, a conductive sheet for a touch panel.

FIG. 35A is a cross-sectional view illustrating, with partial omission,an example of the conductive sheet for the touch panel.

FIG. 35B is a cross-sectional view illustrating, with partial omission,another example of the conductive sheet for the touch panel.

FIG. 36 is a plan view illustrating an example of a first electrodepattern formed on a first conductive sheet.

FIG. 37 is a plan view illustrating an example of a second electrodepattern formed on a second conductive sheet.

FIG. 38 is a plan view illustrating, with partial omission, an examplein which the first conductive sheet and the second conductive sheet arecombined with each other to form a conductive sheet for a touch panel.

FIG. 30 is a schematic view illustrating a positional relation between ametal thin wire and a break part.

FIG. 40 is a schematic view illustrating a relation between a centralposition of the metal thin wire and a central position of the breakpart.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

Hereinafter, preferred embodiments of the present invention aredescribed with reference to the attached drawings. The present inventionis described by way of the following preferred embodiments, but can bechanged according to many methods, without departing from the scope ofthe present invention. Other embodiments than the present embodimentscan be adopted for the present invention. Accordingly, all changeswithin the scope of the present invention are included in the scope ofthe patent claims. Note that, herein, “to” indicating a numerical valuerange is used to mean that the numerical value range includes numericalvalues given before and after “to” as its lower limit value and itsupper limit value.

FIG. 1 is a schematic plan view of a conductive sheet 1 for a touchpanel. The conductive sheet 1 includes a first electrode pattern 10 madeof metal thin wires and a second electrode pattern 40 made of metal thinwires. The first electrode pattern 10 includes a plurality of firstconductive patterns 12 that extend in a first direction (X direction)and are arranged in parallel to each other. The second electrode pattern40 includes a plurality of second conductive patterns 42 that extend ina second direction (Y direction) orthogonal to the first direction (Xdirection) and are arranged in parallel to each other.

Each first conductive pattern 12 has one end electrically connected to afirst electrode terminal 14. Further, each first electrode terminal 14is electrically connected to a first wire 16 having conductiveproperties. Each second conductive pattern 42 has one end electricallyconnected to a second electrode terminal 44. Each second electrodeterminal 44 is electrically connected to a second wire 46 havingconductive properties.

FIG. 2 is a schematic cross-sectional view of the conductive sheet 1according to the present embodiment. The conductive sheet 1 includes: asubstrate 30 having a first main surface and a second main surface; thefirst electrode pattern 10 placed on the first main surface of thesubstrate 30; and the second electrode pattern 40 placed on the secondmain surface of the substrate 30. The first electrode pattern 10includes the first conductive patterns 12, and each first conductivepattern 12 includes sub-nonconduction patterns 18 electrically separatedfrom the first conductive pattern 12. In the embodiment of FIG. 2,adjacent two of the first conductive patterns 12 are illustrated, andeach first conductive pattern 12 includes two sub-nonconduction patterns18. The present invention, however, is not limited thereto.

FIG. 3 is a view of a state where a finger 500 is brought into contactwith a touch panel including the conductive sheet 1 of FIG. 2. If thefinger 500 is brought into contact with the first conductive patterns 12including the sub-nonconduction patterns 18, lines of electric forcedischarged from the second conductive patterns 42 pass through thesub-nonconduction patterns 18. That is, the lines of electric force arenot closed between the first conductive patterns 12 and the secondconductive patterns 42. As a result, a change in electrostaticcapacitance caused by the touch with finger 500 can be reliablyrecognized.

FIG. 4 is a view of a state where the finger 500 is brought into contactwith a touch panel including a conventional conductive sheet 101. Theconductive sheet 101 includes: a substrate 300 having a first mainsurface and a second main surface; a first electrode pattern 110 placedon the first main surface of the substrate 300; and a second electrodepattern 400 placed on the second main surface of the substrate 300. Eachfirst conductive pattern 120 of the first electrode pattern 110 does notinclude a sub-nonconduction pattern electrically separated from thefirst conductive pattern 120. That is, each first conductive pattern 120is made of a uniform conductive region. As a result, lines of electricforce discharged from second conductive patterns 420 are closed betweenthe first conductive patterns 120 and the second conductive patterns420, and the touch with finger 500 cannot be detected in some cases.

In the conductive sheet 1 according to one aspect, each first conductivepattern 12 includes, inside thereof, the sub-nonconduction patterns IKelectrically separated from the first conductive pattern 12. Further,assuming that the area of each first conductive pattern 12 is A and thatthe area of the sub-nonconduction patterns 18 is B, a relation of5%<B/(A+B)<97% is satisfied. The area A is the entire area from one endto another end of one first conductive pattern 12, and the area B is thearea of the sub-nonconduction patterns IK included from one end toanother end of one first conductive pattern 12. In another embodiment, arelation of 10%≤B/(A+B)≤80% is satisfied. In still another embodiment, arelation of 10%≤B/(A+B)≤60% is satisfied.

<<First Electrode Pattern>>

First Embodiment

FIG. 5 illustrates a conductive sheet 1 including a first electrodepattern 10 according to a first embodiment. In FIG. 5, the firstelectrode pattern 10 includes two types of first conductive patterns 12formed by a plurality of grids 26 made of metal thin wires. Theplurality of grids 26 have substantially uniform shapes. Here, thesubstantially uniform means not only that the shapes are completelycoincident with each other but also that the shapes and sizes of thegrids 26 are seemingly the same as each other.

Each first conductive pattern 12 has one end electrically connected to afirst electrode terminal 14. Each first electrode terminal 14 iselectrically connected to one end of each first wire 16. Each first wire16 has another end electrically connected to a terminal 20. Each firstconductive pattern 12 is electrically separated by a first nonconductivepattern 28.

Note that, in the case of the use of the conductive sheet 1 as atransparent conductive film placed on the front side of a display thatis required to have visibility, a dummy pattern that includes breakparts to be described later and is made of metal wires is formed as thefirst nonconductive pattern 28. On the other hand, in the case of theuse of the conductive sheet 1 as a transparent conductive film placed onthe front side of a notebook computer, a touch pad, or the like that isnot particularly required to have visibility, a dummy pattern made ofmetal thin wires is not formed as the first nonconductive pattern 28,and the first nonconductive pattern 28 exists as a space (blank).

The first conductive patterns 12 extend in a first direction (Xdirection), and are arranged in parallel. Each first conductive pattern12 includes slit-like sub-nonconduction patterns 18 electricallyseparated from the first conductive pattern 12. Each first conductivepattern 12 includes a plurality of first conductive pattern lines 22divided by the sub-nonconduction patterns 18.

Note that, in the case of the use of the conductive sheet 1 as atransparent conductive film placed on the front side of a display thatis required to have visibility, a dummy pattern that includes breakparts to be described later and is made of metal wires is formed as eachsub-nonconduction pattern 18. On the other hand, in the case of the useof the conductive sheet 1 as a transparent conductive film placed on thefront side of a notebook computer, a touch pad, or the like that is notparticularly required to have visibility, a dummy pattern made of metalthin wires is not formed as each sub-nonconduction pattern 18, and eachsub-nonconduction pattern 18 exists as a space (blank).

As illustrated in the upper side of FIG. 5, a first first conductivepattern 12 includes slit-like sub-nonconduction patterns 18 each havinganother end that is opened. Because the another ends are opened, thefirst first conductive pattern 12 has a comb-shaped structure. In thepresent embodiment, the first first conductive pattern 12 includes twosub-nonconduction patterns 18, whereby three first conductive patternlines 22 are formed. The first conductive pattern lines 22 are connectedto the first electrode terminal 14, and thus have the same electricpotential.

As illustrated in the lower side of FIG. 5, still another firstconductive pattern 12, that is, a second first conductive pattern 12 hasanother end at which an additional first electrode terminal 24 isprovided. Slit-like sub-nonconduction patterns 18 are closed inside ofthe first conductive pattern 12. If the additional first electrodeterminal 24 is provided, each first conductive pattern 12 can be easilychecked. In the present embodiment, the second first conductive pattern12 includes two closed sub-nonconduction patterns 18, whereby threefirst conductive pattern lines 22 are formed in the first conductivepattern 12. Each first conductive pattern lines 22 is connected to thefirst electrode terminal 14 and the additional first electrode terminal24, and thus they have the same electric potential. Such firstconductive pattern lines are one of modified examples of the comb-shapedstructure.

The number of the first conductive pattern lines 22 may be two or more,and is determined within a range of ten or less and preferably a rangeof seven or less, in consideration of a relation with a pattern designof metal thin wires.

Moreover, the pattern shapes of the metal thin wires of the three firstconductive pattern lines 22 may be the same as each other, and may bedifferent from each other. In FIG. 5, the shapes of the first conductivepattern lines 22 are different from each other. In the first firstconductive pattern 12, the uppermost first conductive pattern line 22 ofthe three first conductive pattern lines 22 is designed to extend alongthe first direction (X direction) such that adjacent mountain-shapedmetal wires intersect with each other. The grids 26 of the uppermostfirst conductive pattern line 22 are not complete, that is, each grid 26does not have a lower apex angle. The central first conductive patternline 22 is designed to extend in two lines along the first direction (Xdirection) such that sides of adjacent ones of the grids 26 are incontact with each other. The lowermost first conductive pattern line 22is designed to extend along the first direction (X direction) such thatapex angles of adjacent ones of the grids 26 are in contact with eachother and that sides of the grids 26 are extended.

In the second first conductive pattern 12, the uppermost firstconductive pattern line 22 and the lowermost first conductive patternline 22 have substantially the same grid shape, and are thus designed toextend in two lines along the first direction (X direction) such thatsides of adjacent ones of the grids 26 are in contact with each other.In the second first conductive pattern 12, the central first conductivepattern line 22 is designed to extend along the first direction (Xdirection) such that apex angles of adjacent ones of the grids 26 are incontact with each other and that sides of the grids 26 are extended.

In the first embodiment, assuming that the area of each first conductivepattern 12 is A1 and that the area of the sub-nonconduction patterns 18is B1, it is preferable that 10%≤B1/(A1+B1)≤80% be satisfied, and it isfurther preferable that 40%≤B1/(A1+B1)≤60% be satisfied. If this rangeis satisfied, a difference in electrostatic capacitance between when afinger is in contact with the conductive sheet 1 and when a finger isnot in contact with the conductive sheet 1 can be made larger. That is,the detection accuracy of the touch with finger can be improved.

Note that each area can be obtained in the following manner. A virtualline in contact with a plurality of the first conductive pattern lines22 is drawn, and the first conductive pattern 12 and thesub-nonconduction patterns 18 surrounded by this virtual line arecalculated, whereby each area can be obtained.

Assuming that the total width of the widths of the first conductivepattern lines 22 is Wa and that the sum of: the sum of the widths of thesub-nonconduction patterns 18; and the width of the first nonconductivepattern 28 is Wb, it is preferable that a condition of the followingexpression (W1-1) be satisfied, it is more preferable that a conditionof the following expression (W1-2) be satisfied, and it is morepreferable that a condition of the following expression (W1-3) besatisfied. Moreover, it is preferable that a condition of the followingexpression (W2-1) be satisfied, it is more preferable that a conditionof the following expression (W2-2) be satisfied, and it is morepreferable that a condition of the following expression (W2-3) besatisfied.10%≤(Wa/(Wa+Wb))×100≤80%  (W1-1)10%≤(Wa/(Wa+Wb))×100≤60%  (W1-2)30%≤(Wa/(Wa+Wb))×100≤55%  (W1-3)Wa≤(Wa+Wb)/2  (W2-1)(Wa+Wb)/5≤Wa≤(Wa+Wb)/2  (W2-2)(Wa+Wb)/3≤Wa≤(Wa+Wb)/2  (W2-3)

If the sum of the widths of the first conductive pattern lines 22 issmall, the touch panel response tends to be slower due to an increase inelectrode resistance, whereas the recognition performance for acontacting finger tends to be higher due to a decrease in electrostaticcapacitance. On the other hand, if the sum of the widths of the firstconductive pattern lines 22 is large, the touch panel response tends tobe faster due to a decrease in electrode resistance, whereas therecognition performance for a contacting finger tends to be lower due toan increase in electrostatic capacitance. These are in a trade-offrelation, but, if the range of any of the above expressions issatisfied, the touch panel response and the recognition performance fora finger can be optimized.

Here, as illustrated in FIG. 5, the sum of widths a1, a2, and a3 of thefirst conductive pattern lines 22 corresponds to Wa. and the sum ofwidths b1 and b2 of the sub-nonconduction patterns 18 and a width b3 ofthe first nonconductive pattern 28 corresponds to Wb.

FIG. 5 illustrates one conductive sheet 1 in which the first firstconductive pattern 12 not including the additional first electrodeterminal 24 and the second first conductive pattern 12 including theadditional first electrode terminal 24 are formed on the same plane.However, the first first conductive pattern 12 and the second firstconductive pattern 12 do not necessarily need to be mixedly formed, andonly any one of the first first conductive pattern 12 and the secondfirst conductive pattern 12 may be formed.

In another embodiment, further preferably, assuming that the total widthof the widths of the first conductive pattern lines 22 is Wa and thatthe total width of: the sum of the widths of the sub-nonconductionpatterns 18; and the width of the first nonconductive pattern 28 is Wb,relations of 1.0 mm≤Wa≤5.0 mm and 1.5 mm≤Wb≤5.0 mm are satisfied. Inconsideration of the average size of a human finger, if Wa and Wb arerespectively set within these ranges, the contact position can be moreaccurately detected. Further, for the value of Wa, 1.5 mm≤Wa≤4.0 mm ispreferable, and 2.0 mm≤Wa≤2.5 mm is further preferable. Furthermore, forthe value of Wb, 1.5 mm≤Wb≤4.0 mm is preferable, and 2.0 mm≤Wb≤3.0 mm isfurther preferable.

The metal thin wires that form the first electrode pattern 10 each havea wire width of, for example, 30 μm or less. The metal thin wires thatform the first electrode pattern 10 are made of, for example, metalmaterials such as gold, silver, and copper and conductive materials suchas metal oxides.

It is desirable that the wire width of each metal thin wire be 30 μm orless, preferably 15 μm or less, more preferably 10 μm or less, morepreferably 9 μm or less, and more preferably 7 μm or less, and be 0.5 μmor more and preferably 1 μm or more.

The first electrode pattern 10 includes the plurality of grids 26 madeof metal thin wires that intersect with each other. Each grid 26includes an opening region surrounded by the metal thin wires. Each grid26 has one side having a length of 900 μm or less and 250 μm or more. Itis desirable dial the length of one side thereof be 700 μm or less and300 μm or more.

In the first conductive patterns 12 of the present embodiment, theopening ratio is preferably 85% or more, further preferably 90% or more,and most preferably 95% or more, in terms of the visible lighttransmittance. The opening ratio corresponds to the percentage of atranslucent portion of the first electrode pattern 10 excluding themetal thin wires, in a predetermined region.

In the above-mentioned conductive sheet 1, each grid 26 has asubstantially rhomboid shape. Alternatively, each grid 26 may have otherpolygonal shapes.

Moreover, the shape of one side of each grid 26 may be a curved shape ora circular arc shape instead of a straight shape. In the case of thecircular arc shape, for example, opposing two of the sides of each grid26 may each have a circular arc shape convex outward, and anotheropposing two of the sides thereof may each have a circular arc shapecorn ex inward. Moreover, the shape of each side of each grid 26 may bea wavy shape in which a circular arc convex outward and a circular arcconvex inward are alternately continuous. As a matter of course, theshape of each side thereof may be a sine curve.

Next, examples of other first electrode patterns of the first embodimentare described with reference to FIGS. 6 to 11.

FIG. 6 illustrates the first electrode pattern 10 according toembodiment. The first electrode pattern 10 includes the first conductivepatterns 12 formed by the large number of grids 26 made of metal thinwires. The first conductive patterns 12 extend in the first direction (Xdirection). Each first conductive pattern 12 includes the slit-likesub-nonconduction patterns 18 for electrically separating the firstconductive pattern 12. Each first conductive pattern 12 includes theplurality of first conductive pattern lines 22 divided by thesub-nonconduction patterns 18. As illustrated in FIG. 6, each firstconductive pattern line 22 is formed by the plurality of grids 26 thatare arranged in one line in the first direction (X direction). The firstconductive pattern lines 22 are electrically connected to each other bythe large number of grids 26 that are made of metal thin wires and areplaced at an end.

As illustrated in FIG. 6, the first conductive pattern lines 22respectively extend in the first direction (X direction) from the firstgrid, the third grid, and the fifth grid of the five grids 26 that arearranged in the second direction (Y direction) at the end. As a result,each of the widths a1, a2, and a3 of the first conductive pattern 12 andeach of the widths b1 and b2 of the sub-nonconduction patterns 18 aresubstantially the same length (as long as the diagonal of each grid 26).

FIG. 7 illustrates the first electrode pattern 10 according toembodiment. The same configurations as those described above aredesignated by the same reference numerals or reference characters, anddescription thereof may be omitted. The first electrode pattern 10includes the first conductive patterns 12 formed by the large number ofgrids 26 made of metal thin wires. The first conductive patterns 12extend in the first direction (X direction). Each first conductivepattern 12 includes the slit-like sub-nonconduction patterns 18 forelectrically separating the first conductive pattern 12. As illustratedin FIG. 7, each first conductive pattern line 22 is formed by theplurality of grids 26 that are arranged in one line in the firstdirection (X direction).

Unlike FIG. 6, in FIG. 7, the first conductive pattern lines 22respectively extend in the first direction (X direction) from the firstgrid, between the third grid and the fourth grid, and the sixth grid ofthe six grids 26 that are arranged in the second direction (Ydirection). That is, compared with FIG. 6, the plurality of firstconductive pattern lines 22 in FIG. 7 are arranged at a pitch longer byhalf the size of each grid 26. As a result, the widths b1 and b2 of thesub-nonconduction patterns 18 are larger than the widths a1, a2, and a3of the first conductive pattern 12. The widths b1 and b2 of thesub-nonconduction patterns 18 are 1.5 times longer than the diagonal ofeach grid 26, and the widths a1, a2, and a3 of the first conductivepattern 12 are as long as the diagonal of each grid 26. In the firstelectrode pattern 10 of FIG. 7, the width of each sub-nonconductionpattern 18 is larger.

FIG. 8 illustrates the first electrode pattern 10 according toembodiment. The same configurations as those of the first electrodepattern 10 described above are designated by the same reference numeralsor reference characters, and description thereof may be omitted. Thefirst electrode pattern 10 includes the first conductive patterns 12formed by the large number of grids 26 made of metal thin wires. Thefirst conductive patterns 12 extend in the first direction (Xdirection). Each first conductive pattern 12 includes the slit-likesub-nonconduction patterns 18 for electrically separating the firstconductive pattern 12. As illustrated in FIG. 8, each first conductivepattern line 22 is formed by the plurality of grids 26 that are arrangedin two lines in the first direction (X direction).

In FIG. 8, the first conductive pattern lines 22 respectively extend intwo lines in the first direction (X direction) from the first grid, thethird grid and the fourth grid, and the fifth grid and the sixth grid ofthe six grids 26 that are arranged in the second direction (Ydirection). As a result, the widths b1 and b2 of the sub-nonconductionpatterns 18 are smaller than the widths a1, a2, and a3 of the firstconductive pattern 12. The widths b1 and b2 of the sub-nonconductionpatterns 18 are as long as the diagonal of each grid 26, and the widthsa1, a2, and a3 of the first conductive pattern 12 are 1.5 limes longerthan the diagonal of each grid 26. In the first electrode pattern 10 ofFIG. 8, the width of the first conductive pattern 12 is larger.

FIG. 9 illustrates the first electrode pattern 10 according toembodiment. The same configurations as those of the first electrodepattern 10 described above are designated by the same reference numeralsor reference characters, and description thereof may be omitted. Thefirst electrode pattern 10 illustrated in FIG. 9 has basically the samestructure as that of the first electrode pattern 10 illustrated in FIG.6. FIG. 9 is different from FIG. 6 in the following point. In FIG. 9,joining parts 27 that electrically connect the first conductive patternlines 22 to each other are provided at locations other than ends of thefirst conductive pattern lines 22. Because the joining parts 27 areprovided, even if the first conductive pattern lines 22 become longerand the wiring resistance thus becomes larger, the first conductivepattern lines 22 can be kept at the same electric potential.

FIG. 10 illustrates the first electrode pattern 10 according toembodiment. The same configurations as those of the first electrodepattern 10 described above are designated by the same reference numeralsor reference characters, and description thereof may be omitted. Thefirst electrode pattern 10 illustrated in FIG. 10 has basically the samestructure as that of the first electrode pattern 10 illustrated in FIG.6. Unlike FIG. 6, in FIG. 10, the number of the first conductive patternlines 22 is not three but two. The finger detection accuracy can be madehigher as long as the number of the first conductive pattern lines 22 ofthe first electrode pattern 10 is two or more.

FIG. 11 illustrates the first electrode pattern 10 according toembodiment. The same configurations as those of the first electrodepattern 10 described above are designated by the same reference numeralsor reference characters, and description thereof may be omitted. Thefirst electrode pattern 10 illustrated in FIG. 11 has basically the samestructure as that of the first electrode pattern 10 illustrated in FIG.6. Unlike FIG. 6, in FIG. 11, the number of the first conductive patternlines 22 is not three but four. The finger detection accuracy can bemade higher as long as the number of the first conductive pattern lines22 of the first electrode pattern 10 is two or more, for example, evenfive or more.

Note that, in FIG. 6 to FIG. 11, each area can be obtained in thefollowing manner. A virtual line in contact with a plurality of thefirst conductive pattern lines 22 is drawn, and the first conductivepattern 12 and the sub-nonconduction patterns 18 surrounded by thisvirtual line are calculated, whereby each area can be obtained.

Second Embodiment

FIG. 12 illustrates a conductive sheet 1 including a first electrodepattern 10 according to another embodiment. Configurations similar tothose in FIG. 5 are designated by the same reference numerals orreference characters, and description thereof may be omitted. In FIG.12, the first electrode pattern 10 includes two types of firstconductive patterns 12 formed by a plurality of grids 26 made of metalthin wires. The plurality of grids 26 have substantially uniform shapes.Here, the substantially uniform means not only that the shapes arecompletely coincident with each other but also that the shapes and sizesof the grids 26 are seemingly the same as each other.

Each first conductive pattern 12 has one end electrically connected to afirst electrode terminal 14. Each first electrode terminal 14 iselectrically connected to one end of each first wire 16. Each first wire16 has another end electrically connected to a terminal 20. Each firstconductive pattern 12 is electrically separated by a first nonconductivepattern 28.

Note that, in the case where the conductive sheet 1 is used as atransparent conductive film placed on the front side of a display thatis required to have visibility, a dummy pattern that includes breakparts to be described later and is made of metal wires is formed as thefirst nonconductive pattern 28. On the other hand, in the case where theconductive sheet 1 is used as a transparent conductive film placed onthe front side of a notebook computer, a touch pad, or the like that isnot particularly required to have visibility, a dummy pattern made ofmetal thin wires is not formed as the first nonconductive pattern 28,and the first nonconductive pattern 28 exists as a space (blank).

As illustrated in the upper side of FIG. 12, one first conductivepattern, that is, a first first conductive pattern 12 does not includean additional first electrode terminal 24. On the other hand, asillustrated in the lower side of FIG. 12, a second first conductivepattern 12 includes the additional first electrode terminal 24. FIG. 12illustrates one conductive sheet 1 in which the first first conductivepattern 12 not including the additional first electrode terminal 24 andthe second first conductive pattern 12 including the additional firstelectrode terminal 24 are formed on the same plane. However, the firstfirst conductive pattern 12 and the second first conductive pattern 12do not necessarily need to be mixedly formed, and only any one of thefirst first conductive pattern 12 and the second first conductivepattern 12 may be formed.

In the present embodiment, each first conductive pattern 12 has X-shapedstructures with cyclical intersections. This cycle can be selected asappropriate. Assuming that the area of each first conductive pattern 12is A2 and that the area of the sub-nonconduction patterns 18 is B2, arelation of 10%≤B2/(A2+B2)≤80% is satisfied. In another embodiment, arelation of 20%≤B2/(A2+B2)≤50% is satisfied. In still anotherembodiment, a relation of 30%≤B2/(A2+B2)≤50% is satisfied.

Note that each area can be obtained in the following manner. The area ofeach first conductive pattern 12 is obtained by calculating the unitarea of each grid 26×the number of the grids 26. The area of thesub-nonconduction patterns 18 is obtained by placing virtual grids 26and calculating the unit area of each virtual grid 26×the number of thegrids 26.

Note that, in the case where the conductive sheet 1 is used as atransparent conductive film placed on the front side of a display thatis required to have visibility, a dummy pattern that includes breakparts to be described later and is made of metal wires is formed as eachsub-nonconduction pattern 18. On the other hand, in the case where theconductive sheet 1 is used as a transparent conductive film placed onthe front side of a notebook computer, a touch pad, or the like that isnot particularly required to have visibility, a dummy pattern made ofmetal thin wires is not formed as each sub-nonconduction pattern 18, andeach sub-nonconduction pattern 18 exists as a space (blank).

If this range is satisfied, a difference in electrostatic capacitancebetween when a finger contacts the conductive sheet 1 and when a fingerdoes not contact the conductive sheet 1 can be made larger. That is, thedetection accuracy of the touch with finger can be improved.

The wire width of the metal thin wires that form the first electrodepattern 10 and the material thereof are substantially the same as thosein the embodiment of FIG. 5. Moreover, the grids 26 of the metal thinwires that form the first electrode pattern 10 are substantially thesame as those in the embodiment of FIG. 5.

Next, examples of other first electrode patterns of the secondembodiment are described with reference to FIGS. 13 to 22.

FIG. 13 illustrates the first electrode pattern 10 according to anotherembodiment. The same configurations as those of the first electrodepattern 10 described above are designated by the same reference numeralsor reference characters, and description thereof may be omitted. Thefirst electrode pattern 10 includes the first conductive patterns 12formed by the large number of grids 26 made of metal thin wires. Eachfirst conductive pattern 12 includes the plurality of sub-nonconductionpatterns 18 along the first direction, to thereby have X-shapedstructures with cyclical intersections.

In the first conductive pattern 12 illustrated in FIG. 13, eachsub-nonconduction pattern 18 is surrounded and defined by four sides.Each of the four sides is formed by linearly arranging the plurality ofgrids 26 with sides of adjacent ones of the grids 26 being connected toeach other. Each sub-nonconduction pattern 18 is surrounded by theplurality of linearly arranged grids 26, whereby a diamond pattern(rhomboid pattern) is formed. Adjacent diamond patterns are electricallyconnected to each other. In FIG. 13, adjacent diamond patterns areelectrically connected to each other with the intermediation of sides ofthe grids 26.

FIG. 14 illustrates the first electrode pattern 10 according to anotherembodiment. The same configurations as those of the first electrodepattern 10 described above are designated by the same reference numeralsor reference characters, and description thereof may be omitted. Thefirst electrode pattern 10 includes the first conductive patterns 12formed by the large number of grids 26 made of metal thin wires. Eachfirst conductive pattern 12 includes the plurality of sub-nonconductionpatterns 18 along the first direction, to thereby have X-shapedstructures with cyclical intersections.

In the first conductive pattern 12 illustrated in FIG. 14, eachsub-nonconduction pattern 18 is surrounded and defined by four sides.Each of the four sides is formed by linearly arranging, in multiplestages, the plurality of grids 26 with sides of adjacent ones of thegrids 26 being connected to each other. In FIG. 14, each of the foursides is formed in two stages, but is not limited to the two stages.

FIG. 15 illustrates the first electrode pattern 10 according to anotherembodiment. The same configurations as those of the first electrodepattern 10 described above are designated by the same reference numeralsor reference characters, and description thereof may be omitted. Thefirst electrode pattern 10 includes the first conducts e patterns 12formed by the large number of grids 26 made of metal thin wires. Eachfirst conductive pattern 12 includes the plurality of sub-nonconductionpatterns 18 along the first direction, to thereby have X-shapedstructures with cyclical intersections.

In the first conducts e pattern 12 illustrated in FIG. 15, eachsub-nonconduction pattern 18 is surrounded and defined by six sides.Four of the six sides are formed by linearly arranging the plurality ofgrids 26 with sides of adjacent ones of the grids 26 being connected toeach other. Two of the six sides are formed by linearly arranging theplurality of grids 26 with apex angles of adjacent ones of the grids 26being connected to each other.

FIG. 16 illustrates the first electrode pattern 10 according to anotherembodiment. The some configurations as those of the first electrodepattern 10 described above are designated by the same reference numeralsor reference characters, and description thereof may be omitted. Thefirst electrode pattern 10 includes the first conductive patterns 12formed by the large number of grids 26 made of metal thin wires. Eachfirst conductive pattern 12 includes the plurality of sub-nonconductionpatterns 18 along the first direction, to thereby have X-shapedstructures with cyclical intersections.

The first conductive pattern 12 illustrated in FIG. 16 is the same inthe shape of each sub-nonconduction pattern 18 as the first conductivepattern 12 illustrated in FIG. 13. However, unlike FIG. 13, in FIG. 16,adjacent diamond patterns are electrically connected to each other atapex angles of the grids 26, that is, at one point. The shape of eachsub-nonconduction pattern 18 is not limited to the diamond pattern.

FIG. 17 illustrates the first electrode pattern 10 according to anotherembodiment. The some configurations as those of the first electrodepattern 10 described above are designated by the same reference numeralsor reference characters, and description thereof may be omitted. Thefirst electrode pattern 10 includes the first conductive patterns 12formed by the large number of grids 26 made of metal thin wires. Eachfirst conductive pattern 12 includes the plurality of sub-nonconductionpatterns 18 along the first direction, to thereby have X-shapedstructures with cyclical intersections.

In FIG. 17, the shapes of diamond patterns are alternately different,and the sizes of adjacent ones of the sub-nonconduction patterns 18 aredifferent. That is, the same shape appears every two cycles. However,not limited to every two cycles, the same shape may appear every threecycles or every four cycles.

FIG. 18 illustrates the first electrode pattern 10 according to anotherembodiment. The same configurations as those of the first electrodepattern 10 described above are designated by the same reference numeralsor reference characters, and description thereof may be omitted. Thefirst electrode pattern 10 includes the first conductive patterns 12formed by the large number of grids 26 made of metal thin wires. Eachfirst conductive pattern 12 includes the plurality of sub-nonconductionpatterns 18 along the first direction, to thereby have X-shapedstructures with cyclical intersections.

The first conductive pattern 12 illustrated in FIG. 18 has basically thesame shape as that of the first conductive pattern 12 illustrated inFIG. 13. However, the grid 26 located at each apex angle of a diamondpattern is provided with protruding wires 31 made of metal thin wires.

FIG. 19 illustrates the first electrode pattern 10 according to anotherembodiment. The same configurations as those of the first electrodepattern 10 described above are designated by the same reference numeralsor reference characters, and description thereof may be omitted. Thefirst electrode pattern 10 includes the first conductive patterns 12formed by the large number of grids 26 made of metal thin wires. Eachfirst conductive pattern 12 includes the plurality of sub-nonconductionpatterns 18 along the first direction, to thereby have X-shapedstructures with cyclical intersections.

The first conductive pattern 12 illustrated in FIG. 19 has basically thesame shape as that of the first conductive pattern 12 illustrated inFIG. 13. However, the grids 26 that form each side of a diamond patternare provided with the protruding wires 31 made of metal thin wires.

The first electrode pattern 10 illustrated in each of FIGS. 18 and 19 isprovided with the protruding wires 31, and hence a sensor region fordetecting the contact of a finger can be widened.

FIG. 20 illustrates the first electrode pattern 10 according to anotherembodiment. The same configurations as those of the first electrodepattern 10 described above are designated by the same reference numeralsor reference characters, and description thereof may be omitted. Thefirst electrode pattern 10 includes the first conductive patterns 12formed by the large number of grids 26 made of metal thin wires. Eachfirst conductive pattern 12 includes the plurality of sub-nonconductionpatterns 18 along the first direction, to thereby have X-shapedstructures in which grids 26 are not present at the intersection points.In the first conductive pattern 12 illustrated in FIG. 20, the pluralityof grids 26 are arranged in a zigzag manner. Two groups of the gridsarranged in the zigzag manner are opposedly placed so as not to contacteach other, and hence the X-shaped structures without intersectionpoints are formed. Because the X-shaped structures are formed by the twogroups of the grids arranged in the zigzag manner, the electrode patterncan be made thinner, and a contact position of a finger can be finelydetected.

FIG. 21 illustrates the first electrode pattern 10 according to anotherembodiment. The same configurations as those of the first electrodepattern 10 described above are designated by the same reference numeralsor reference characters, and description thereof may be omitted, fivefirst electrode pattern 10 includes the first conductive patterns 12formed by the large number of grids 26 made of metal thin wires. Eachfirst conductive pattern 12 includes the plurality of sub-nonconductionpatterns 18 along the first direction, to thereby have X-shapedstructures in which the grids 26 are not present at the intersectionpoints. In the first conductive pattern 12 illustrated in FIG. 21, theplurality of grids 26 are placed in each corner part in which two groupsof the grids arranged in a zigzag manner approach each other, unlike thefirst conductive pattern 12 illustrated in FIG. 20.

FIG. 22 illustrates the first electrode pattern 10 according to anotherembodiment. The same configurations as those of the first electrodepattern 10 described above are designated by the same reference numeralsor reference characters, and description thereof may be omitted. Thefirst electrode pattern 10 of FIG. 22 includes two first conductivepatterns 12 formed by the large number of grids 26 made of metal thinwires. Each first conductive pattern 12 includes the sub-nonconductionpatterns 18 along the first direction, to thereby have X-shapedstructures with cyclical intersections.

As illustrated in FIG. 22, the upper first conductive pattern 12includes the sub-nonconduction patterns 18 having the same shape alongthe first direction (X direction). Moreover, as illustrated in FIG. 22,the lower first conductive pattern 12 includes the sub-nonconductionpatterns 18 having the same shape along the first direction. Meanwhile,the shapes of the sub-nonconduction patterns 18 are different betweenthe upper first conductive pattern 12 and the lower first conductivepattern 12. The first conductive patterns 12 having different shapes arealternately arranged. Such arrangement as described above secures thedegree of freedom in arrangement of the first electrode pattern 10.

Note that, in the pattern illustrated in each of FIG. 13 to FIG. 22, thearea of each first conductive pattern 12 is obtained by calculating theunit area of each grid 26×the number of the grids 26. The area of thesub-nonconduction patterns 18 is obtained by placing virtual grids 26and calculating the unit area of each virtual grid 26×the number of thegrids 26.

<<Second Electrode Pattern>>

Next, a second electrode pattern is described with reference to thedrawings. As illustrated in FIG. 23, a second electrode pattern 40 isformed by a large number of grids made of metal thin wires. The secondelectrode pattern 40 includes a plurality of second conductive patterns42 that extend in a second direction (Y direction) orthogonal to thefirst direction (X direction) and are arranged in parallel. Each secondconductive pattern 42 is electrically separated by a secondnonconductive pattern 58.

Note that, in the case where the conductive sheet 1 is used as atransparent conductive film placed on the front side of a display thatis required to have visibility, a dummy pattern that includes breakparts to be described later and is made of metal wires is formed as thesecond nonconductive pattern 58. On the other hand, in the case wherethe conductive sheet 1 is used as a transparent conductive film placedon the front side of a notebook computer, a touch pad, or the like thatis not particularly required to have visibility, a dummy pattern made ofmetal thin wires is not formed as the second nonconductive pattern 58,and the second nonconductive pattern 58 exists as a space (blank).

Each second conductive pattern 42 is electrically connected to a secondelectrode terminal 44. Each second electrode terminal 44 is electricallyconnected to a second wire 46 having conductive properties. Each secondconductive pattern 42 has one end electrically connected to the secondelectrode terminal 44. Each second electrode terminal 44 is electricallyconnected to one end of each second wire 46. Each second wire 46 hasanother end electrically connected to a terminal 50. Each secondconductive pattern 42 has a strip-shaped structure having asubstantially constant width along the second direction. However, eachsecond conductive pattern 42 is not limited to the strip shape.

The second electrode pattern 40 may be provided with an additionalsecond electrode terminal 54 at another end thereof. If the additionalsecond electrode terminal 54 is provided, each second conductive pattern42 can be easily checked.

FIG. 23 illustrates one conductive sheet 1 in which the secondconductive pattern 42 not including the additional second electrodeterminal 54 and the second conductive pattern 42 including theadditional second electrode terminal 54 are formed on the same plane.However, such two types of the second conductive patterns 42 do notnecessarily need to be mixedly formed, and only one of the two types ofthe second conductive patterns 42 may be formed.

The metal thin wires that form the second electrode pattern 40 havesubstantially the same wire width and are made of substantially the samematerial as the metal thin wires that form the first electrode pattern10. The second electrode pattern 40 includes a plurality of grids 56made of metal thin wires that intersect with each other, and each grid56 has substantially the same shape as that of each grid 26. The lengthof one side of each grid 56 and the opening ratio of each grid 56 areequivalent to those of each grid 26.

<<Combination Pattern>>

FIG. 24 is a plan view of the conductive sheet 1 in which the firstelectrode pattern 10 including the first conductive patterns 12 eachhaving the comb-shaped structure and the second electrode pattern 40including the second conductive patterns 42 each having the strip-shapedstructure are opposedly placed. The first conductive patterns 12 and thesecond conductive patterns 42 are orthogonal to each other, and thefirst electrode pattern 10 and the second electrode pattern 40 form acombination pattern 70.

In this combination pattern, the first electrode pattern 10 notincluding a dummy pattern and the second electrode pattern 40 notincluding a dummy pattern are combined with each other.

In the combination pattern 70, the grids 26 and the grids 56 form smallgrids 76 in lop view. That is, the intersection parts of the grids 26are respectively placed in substantially the centers of the openingregions of the grids 56. Note that each small grid 76 has one sidehaving a length of 125 μm or more and 450 μm or less, and preferably hasone side having a length of 150 μm or more and 350 μm or less. Thiscorresponds to half the length of one side of each of the grids 26 andthe grids 56.

FIG. 25 is a plan view of the conductive sheet 1 in which the firstelectrode pattern 10 including the first conductive patterns 12 eachhaving the X-shaped structures and the second electrode pattern 40including the second conductive patterns 42 each having the strip-shapedstructure are opposedly placed. The first conductive patterns 12 and thesecond conductive patterns 42 are orthogonal to each other, and thefirst electrode pattern 10 and the second electrode pattern 40 form thecombination pattern 70. In the combination pattern 70, the grids 26 andthe grids 56 form the small grids 76, similarly to the first embodiment.

<<Dummy Pattern>>

FIG. 26 is a plan view illustrating an example of the first electrodepattern 10 of the first embodiment, in which dummy patterns areexplicitly illustrated. The first nonconductive pattern 28 is made ofmetal thin wires similarly to the first conductive patterns 12, andincludes the break parts. Moreover, the sub-nonconduction patterns 18formed in each first conductive pattern 12 are made of metal thin wiressimilarly to the first conductive patterns 12, and include the breakparts. The sub-nonconduction patterns 18 and the first nonconductivepattern 28 are made of metal thin wires including the break pans, andthus are each formed as a so-called dummy pattern electrically separatedfrom the first conductive patterns 12. If the dummy patterns are formed,the first electrode pattern 10 is formed by the grids of the metal thinwires placed at regular intervals. This can prevent a decrease invisibility. Note that, in FIG. 26, the dummy patterns are portionssurrounded by broken lines, and are at positions respectivelycorresponding to the sub-nonconduction patterns 18 and the firstnonconductive pattern 28.

FIG. 27 is an enlarged view of a portion surrounded by a circle in FIG.26. As illustrated in FIG. 27, the metal thin wires that form the firstnonconductive pattern 28 and the sub-nonconduction pattern 18 includebreak parts 29, and are electrically separated from the first conductivepattern 12. It is preferable that each break part 29 be formed in aportion other than each intersection part of the metal thin wires.

In FIG. 27, in order to clarity the first conductive pattern 12, thefirst nonconductive pattern 28, and the sub-nonconduction pattern 18,the wire width of the first conductive pattern 12 is exaggeratinglythickened, and the wire widths of the first nonconductive pattern 28 andthe sub-nonconduction pattern 18 are exaggeratingly thinned.

All the grids 26 that form the first nonconductive pattern 28 and thesub-nonconduction pattern 18 do not necessarily need to include thebreak parts 29. The length of each break part 29 is preferably 60 μm orless, and is more preferably 10 to 50 μm, 15 to 40 μm, and 20 to 40 μm.Such dummy patterns can be formed in the first electrode pattern 10 ofthe first embodiment illustrated in FIG. 5 to FIG. 11.

FIG. 28 is a plan view illustrating an example of the first electrodepattern 10 of the second embodiment including dummy patterns. The firstnonconductive pattern 28 is made of metal thin wires similarly to thefirst conductive patterns 12. Moreover, the sub-nonconduction patterns18 formed in each first conductive pattern 12 are made of metal thinwires similarly to the first conductive patterns 12. Thesub-nonconduction patterns 18 and the first nonconductive pattern 28 aremade of metal thin wires, and thus are each formed as a so-called dummypattern electrically separated from the first conductive patterns 12. InFIG. 28, the dummy patterns are portions surrounded by thick solidlines, and are at positions respectively corresponding to thesub-nonconduction patterns 18 and the first nonconductive pattern 28. Ifthe dummy patterns are formed, the first electrode pattern 10 is formedby the grids of the metal thin wires placed at regular intervals. Thiscan prevent a decrease in visibility.

Also in FIG. 28, the metal thin wires that form the dummy patterns asthe first nonconductive pattern 28 and the sub-nonconduction patterns 18include the break parts, and are electrically separated from the firstconductive pattern 12. It is preferable that each break part be formedin a portion other than each intersection part of the metal thin wires.Such dummy patterns can be formed in the first electrode pattern 10 ofthe second embodiment illustrated in FIG. 12 to FIG. 22.

FIG. 29 is a plan view illustrating an example of the second electrodepattern including a dummy pattern. The second nonconductive pattern 58is made of metal thin wires similarly to the second conductive patterns42, and includes the break parts. The second nonconductive pattern 58 ismade of metal thin wires, and thus is formed as a so-called dummypattern electrically separated from the second conductive patterns 42.In FIG. 29, the dummy pattern is a portion surrounded by a broken line,and is at a position corresponding to the second nonconductive pattern58. If the dummy pattern is formed, the second electrode pattern 40 isformed by the grids of the metal thin wires placed at regular intervals.This can prevent a decrease in visibility.

FIG. 30 is an enlarged view of a portion surrounded by a circle in FIG.29. As illustrated in FIG. 30, the metal thin wires that form the secondnonconductive pattern 58 include break parts 59, and are electricallyseparated from the second conductive patterns 42. It is preferable thateach break part 59 be formed at a portion other than each intersectionpart of the metal thin wires.

In FIG. 30, in order to clarify the second conductive patterns 42 andthe second nonconductive pattern 58, the wire widths of the secondconductive patterns 42 are exaggeratingly thickened, and the wire widthof the second nonconductive pattern 58 is exaggeratingly thinned. Notethat the length of each break part 59 is substantially the same as thatof each break part 29 in FIG. 27.

FIG. 31 explicitly illustrates the first nonconductive pattern 28 andthe first conductive patterns 12 that are made of metal thin wires.Moreover, the break parts are provided between the first conductivepatterns 12, and the sub-nonconduction patterns 18 formed as dummypatterns made of metal thin wires are explicitly illustrated. In FIG.31, the dummy patterns are portions surrounded by broken lines, and areat positions respectively corresponding to the first nonconductivepattern 28, the sub-nonconduction patterns 18 and the secondnonconductive pattern 58. If the dummy patterns are formed, the firstelectrode pattern 11) is formed by the grids of the metal thin wiresplaced at regular internals. This can prevent a decrease in visibility.This is particularly effective in the case where the conductive sheet 1is placed on the front side of a display or the like that is required tohave visibility.

Similarly, the second nonconductive pattern 58 is made of metal thinwires similarly to the second conductive patterns 42. The secondnonconductive pattern 58 is made of metal thin wires, and thus is formedas a so-called dummy pattern electrically separated from the secondconductive patterns 42. If the dummy pattern is formed, the secondelectrode pattern 40 is formed by the grids of the metal thin wiresplaced at regular intervals. This can prevent a decrease in visibility.The dummy pattern made of the metal thin wires includes the break parts,and is electrically separated from the first conductive patterns 12 andthe second conductive patterns 42.

FIG. 32 is a plan view of the conductive sheet 1 in which the firstelectrode pattern 10 including dummy patterns and the second electrodepattern 40 including a dummy pattern are placed such that the firstconductive patterns 12 and the second conductive patterns 42 areorthogonal to each other. Each first conductive pattern 12 includes thesub-nonconduction patterns 18 along the first direction at predeterminedintervals, to thereby have X-shaped structures with cyclicalintersections. The first electrode pattern 10 and the second electrodepattern 40 form the combination pattern 70. The first nonconductivepattern 28, the sub-nonconduction patterns 18, and the secondnonconductive pattern 58 are made of metal thin wires. In FIG. 32, thedummy patterns are portions surrounded by thick solid lines, and are atpositions respectively corresponding to the first nonconductive pattern28, the sub-nonconduction patterns 18, and the second nonconductivepattern 58. If the dummy patterns are formed, the first electrodepattern 10 is formed by the grids of the metal thin wires placed atregular intervals. This can prevent a decrease in visibility.

Next, a method of manufacturing the conductive sheet 1 is described.

In the case of manufacturing the conductive sheet 1, for example, aphotosensitive material having an emulsion layer containingphotosensitive silver halide is exposed to light and developed on thefirst main surface of the transparent substrate 30, and a metal silverpart (metal thin wires) and a light transmissive part (opening regions)are respectively formed in the exposed part and the unexposed part,whereby the first electrode pattern 10 may be formed. Note that themetal silver part is further physically developed and/or plated, wherebythe metal silver part may be caused to support conductive metal.

Alternatively, a resist pattern is formed by exposing to light anddeveloping a photoresist film on copper foil formed on the first mainsurface of the transparent substrate 30, and (lie copper foil exposed onthe resist pattern is etched, whereby the first electrode pattern 10 maybe formed.

Alternatively, a paste containing metal fine grains is printed on thefirst main surface of the transparent substrate 30, and the paste isplated with metal, whereby the first electrode pattern 10 may be formed.

The first electrode pattern 10 may be formed by printing on the firstmain surface of the transparent substrate 30, using a screen printingplate or a gravure printing plate. Alternatively, the first electrodepattern 10 may be formed on the first main surface of the transparentsubstrate 30, according to an inkjet process.

The second electrode pattern 40 can be formed on the second main surfaceof the substrate 30, according to a manufacturing method similar to thatfor the first electrode pattern 10.

The first electrode pattern 10 and the second electrode pattern 40 maybe formed by: forming a photosensitive layer to be plated on thetransparent substrate 30 using a plating preprocessing material;exposing the formed layer to light to develop it; and plating the layerso as to form a metal part and a light transmissive part respectively inthe exposed part and the unexposed part. Note that the metal part may befurther physically developed and/or plated so that the metal part can becaused to support conductive metal. Note that more specific contentsthereof are described in, for example. Japanese Patent ApplicationLaid-Open No. 2003-213437, No. 2006-64923, No. 2006-58797, and No.2006-135271.

In a case as illustrated in FIG. 2 where the first electrode pattern 10is formed on the first main surface of the substrate 30 and where thesecond electrode pattern 40 is formed on the second main surface of thesubstrate 30, if a standard manufacturing method (in which the firstmain surface is first exposed to light, and the second main surface isthen exposed to light) is adopted, the first electrode pattern 10 andthe second electrode pattern 40 having desired patterns cannot beobtained in some cases.

In view of the above, the following manufacturing method can bepreferably adopted.

That is, photosensitive silver halide emulsion layers respectivelyformed on both the surfaces of the substrate 30 are collectively exposedto light, whereby the first electrode pattern 10 is formed on one mainsurface of the substrate 30 while the second electrode pattern 40 isformed on another main surface of the substrate 30.

A specific example of the method of manufacturing the conductive sheetaccording to aspects illustrated in FIGS. 1 to 33 is described.

First, an elongated photosensitive material is manufactured. Thephotosensitive material includes: the substrate 30; a photosensitivesilver halide emulsion layer (hereinafter, referred to as firstphotosensitive layer) formed on the first main surface of the substrate30; and a photosensitive silver halide emulsion layer (hereinafter,referred to as second photosensitive layer) formed on another mainsurface of the substrate 30.

Subsequently, the photosensitive material is exposed to light. Thisexposure process includes: a first exposure process performed on thefirst photosensitive layer, in which the substrate 30 is irradiated withlight so that and the first photosensitive layer is exposed to the lightalong a first exposure pattern; and a second exposure process performedon the second photosensitive layer, in which the substrate 30 isirradiated with light so that the second photosensitive layer is exposedto the light along a second exposure pattern (both-surfaces simultaneousexposure).

For example, in the state where the elongated photosensitive material istransported in one direction, the first photosensitive layer isirradiated with first light (parallel light) with the intermediation ofa first photomask, while the second photosensitive layer is irradiatedwith second light (parallel light) with the intermediation of a secondphotomask. The first light is obtained by converting, into parallellight light emitted from a first light source by means of a halfwayfirst collimator lens. The second light is obtained by converting, intoparallel light, light emitted from a second light source by means of ahalfway second collimator lens.

Although description is given above of the case where the two lightsources (the first light source and the second light source) are used,light emitted from one light source may be split by an optical systeminto the first light and the second light, and the first photosensitivelayer and the second photosensitive layer may be irradiated with thefirst light and the second light.

Subsequently, the photosensitive material after the exposure to light isdeveloped, whereby the conductive sheet 1 for the touch panel ismanufactured. The conductive sheet 1 for the touch panel includes: thesubstrate 30; the first electrode pattern 10 that is formed along thefirst exposure pattern on the first main surface of the substrate 30;and the second electrode pattern 40 that is formed along the secondexposure pattern on another main surface of the substrate 30. Note thatthe exposure time and the development time of the first photosensitivelayer and the second photosensitive layer may variously change dependingon the types of the first light source and the second light source, thetype of a developing solution, and the like. Hence preferable numericalvalue ranges therefor cannot be unconditionally determined, but theexposure lime and the development time are adjusted such that thedevelopment rate is 100%.

Then, according to the manufacturing method of the present embodiment,in the first exposure process, the first photomask is, for example,closely placed on the first photosensitive layer, and is irradiated withthe first light emitted from the first light source that is placed so asto be opposed to the first photomask, wherein the first photosensitivelayer is exposed to light. The first photomask includes a glasssubstrate made of transparent soda glass and a mask pattern (firstexposure pattern) formed on the glass substrate. Accordingly, in thefirst exposure process, a portion of the first photosensitive layer isexposed to light, the portion being along the first exposure patternformed on the first photomask. A gap of approximately 2 to 10 μm may beprovided between the first photosensitive layer and the first photomask.

Similarly, in the second exposure process, the second photomask is, forexample, closely placed on the second photosensitive layer, and isirradiated with the second light emitted from the second light sourcethat is placed so as to be opposed to the second photomask, whereby thesecond photosensitive layer is exposed to light. Similarly to the firstphotomask, the second photomask includes a glass substrate made oftransparent soda glass and a mask pattern (second exposure pattern)formed on the glass substrate. Accordingly, in the second exposureprocess, a portion of the second photosensitive layer is exposed tolight, the portion being along the second exposure pattern formed on thesecond photomask. In this case, a gap of approximately 2 to 10 μm may beprovided between the second photosensitive layer and the secondphotomask.

In the first exposure process and the second exposure process, theemission timing of the first light from the first light source and theemission liming of the second light from the second light source may bethe same as each other, and may be different from each other. If theemission timings thereof are the same as each other, the firstphotosensitive layer and the second photosensitive layer can besimultaneously exposed to light in one exposure process, and theprocessing time can be shortened. Meanwhile, in the case where both thefirst photosensitive layer and the second photosensitive layer are notspectrally sensitized, if the photosensitive material is exposed tolight on both the sides thereof, the exposure to light on one sideinfluences image formation on the other side (rear side).

That is, the first light from the first light source that has reachedthe first photosensitive layer is scattered by silver halide grainscontained in the first photosensitive layer, and is transmitted asscattered light through the substrate 30, and part of the scatteredlight reaches even the second photosensitive layer. Consequently, aboundary portion between the second photosensitive layer and thesubstrate 30 is exposed to light over a wide range, so that a latentimage is formed. Hence, the second photosensitive layer is exposed toboth the second light from the second light source and the first lightfrom the first light source. In the case of manufacturing the conductivesheet 1 for the touch panel in the subsequent development process, athin conductive layer substrated on the first light from the first lightsource is formed between the conductive patterns in addition to theconductive pattern (second electrode pattern 40) along the secondexposure pattern, and a desired pattern (a pattern along the secondexposure pattern) cannot be obtained. The same applies to the firstphotosensitive layer.

As a result of intensive studies for avoiding this, the following isfound out. That is, if the thickness of each of the first photosensitivelayer and the second photosensitive layer is set within a particularrange or if the amount of silver applied to each of the firstphotosensitive layer and the second photosensitive layer is specified,silver halide itself absorbs light, and this can restrict lighttransmission to the rear surface. The thickness of each of the firstphotosensitive layer and the second photosensitive layer can be set to 1μm or more and 4 μm or less. The upper limit value thereof is preferably2.5 μm. Moreover, the amount of silver applied to each of the firstphotosensitive layer and the second photosensitive layer is specified to5 to 20 g/m².

In the above-mentioned exposure method of both-surfaces close contacttype, an image defect due to a hindrance to exposure by dust and thelike attached to the sheet surface is problematic. In order to prevailsuch dust attachment, it is known to apply a conductive substance to thesheet, but metal oxides and the like remain even after the process toimpair the transparency of a final product, and conductive polymers havea problem in preserving properties. As a result of intensive studies inview of the above, it is found out that conductive properties necessaryfor prevention of static charge can be obtained by silver halide with areduced binder, and hence the volume ratio of silver/binder of the firstphotosensitive layer and the second photosensitive layer is specified.That is, the volume ratio of silver/binder of each of the firstphotosensitive layer and the second photosensitive layer is 1/1 or more,and is preferably 2/1 or more.

If the thickness, the amount of applied silver, and the volume ratio ofsilver/binder of each of the first photosensitive layer and the secondphotosensitive layer are set and specified as described above, the firstlight from the first light source that has reached the firstphotosensitive layer does not reach the second photosensitive layer.Similarly, the second light from the second light source that hasreached the second photosensitive layer does not reach the firstphotosensitive layer. As a result, in the case of manufacturing theconductive sheet 1 in the subsequent development process, only the firstelectrode pattern 10 along the first exposure pattern is formed on thefirst main surface of the substrate 30, and only the second electrodepattern 40 along the second exposure pattern is formed on the secondmain surface of the substrate 30, so that desired patterns can beobtained.

In this way according to the above-mentioned manufacturing method usingboth-surfaces collective exposure, the first photosensitive layer andthe second photosensitive layer having both conductive properties andsuitability for the both-surfaces exposure can be obtained. Moreover,the same pattern or different patterns can be arbitrarily formed on boththe surfaces of the substrate 30 in one exposure process on thesubstrate 30. This can facilitate formation of the electrodes of thetouch panel, and can achieve a reduction in thickness (a reduction inheight) of the touch panel.

Next, focused description is given of a method of using a silver halidephotographic photosensitive material corresponding to a particularlypreferable aspect, for the conductive sheet 1 according to the presentembodiment.

The method of manufacturing the conductive sheet 1 according to thepresent embodiment includes the following three aspects depending onmodes of the photosensitive material and the development process.

(1) An aspect in which: a silver halide black-and-white photosensitivematerial not including the center of physical development is chemicallydeveloped or thermally developed; and a metal silver part is formed onthe photosensitive material.

(2) An aspect in which: a silver halide black-and-white photosensitivematerial including the center of physical development in a silver halideemulsion layer is dissolved and physically developed; and a metal silverpart is formed on the photosensitive material.

(3) An aspect in which: a silver halide black-and-white photosensitivematerial not including the center of physical development and an imagereceiving sheet having a non-photosensitive layer including the centerof physical development are put on top of each other (overlaid) and thensubjected to diffusion transfer development; and a metal silver part isformed on the non-photosensitive image receiving sheet.

According to the aspect in (1), which is of integrated black-and-whitedevelopment type, a translucent conductive film such as alight-transmissive conductive film is formed on the photosensitivematerial. The obtained developed silver is chemically developed silveror thermally developed silver, and is highly active in the subsequentplating or physical development process, because the obtained developedsilver is a filament having a high-specific surface.

According to the aspect in (2), in the exposed part, silver halidegrains near the center of physical development are dissolved anddeposited on the center of development, whereby a translucent conductivefilm such as a light-transmissive conductive film is formed on thephotosensitive material. This aspect is also of integratedblack-and-white development type. Because the development action isdeposition on the center of physical development, high activity isobtained, and the developed silver has a spherical shape with asmall-specific surface.

According to the aspect in (3), in the unexposed part, silver halidegrains are dissolved and diffused to be deposited on the center ofdevelopment on the image receiving sheet, whereby a translucentconductive film such as a light-transmissive conductive film is formedon the image receiving sheet. This aspect is of so-called separate type,in which the image receiving sheet is separated for use from thephotosensitive material.

In any one of these aspects, both a negative development process and areversal development process can be selected (in the case of a diffusiontransfer method, the use of an auto-positive photosensitive material asthe photosensitive material enables the negative development process).

Here, a configuration of the conductive sheet 1 according to the presentembodiment is described below in detail.

[Substrate 30]

The substrate 30 can be formed using a plastic film, a plastic plate, aglass plate, and the like. Examples of the raw materials of the plasticfilm and the plastic plate include: polyesters such as polyethyleneterephthalate (PET) and polyethylene naphthalate (PEN); polyolefins suchas polyethylene (PE), polypropylene (PP), polystyrene, and ethylenevinyl acetate (EVA)/cycloolefin polymer (COP)/cycloolefin copolymer(COC); vinyl resins; polycarbonate (PC); polyamide; polyimide; acrylicresins; and triacetylcellulose (TAC). In particular, polyethyleneterephthalate (PET) is preferable from the perspective of the lighttransmissivity, the workability, and the like.

[Silver Salt Emulsion Layer]

A silver salt emulsion layer that becomes each of the first electrodepattern 10 and the second electrode pattern 40 of the conductive sheet 1contains additives such as a solvent and a colorant in addition to asilver salt and a binder.

Examples of the silver salt used in the present embodiment includeinorganic silver salts such as silver halide and organic silver saltssuch as silver acetate. In the present embodiment, it is preferable touse silver halide excellent in characteristics as an optical sensor.

The amount of silver (the amount of silver salt) applied to the silversalt emulsion layer is preferably 1 to 30 g/m², more preferably 1 to 25g/m², and further preferably 5 to 20 g/m², in terms of silver. If theamount of applied silver is set within this range, a desired surfaceresistance can be obtained in the case of manufacturing the conductivesheet 1 for the touch panel.

Examples of the binder used in the present embodiment include gelatin,polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), polysaccharidessuch as starch, cellulose and derivatives thereof, polyethylene oxide,polyvinylamine, chitosan, poly lysine, polyacrylic acid, polyalginicacid, polyhyaluronic acid, and carboxy cellulose. These substances eachexhibit a neutral, anionic, or cationic property depending on theionicity of a functional group thereof.

The content of the binder in the silver salt emulsion layer is notparticularly limited, and can be determined as appropriate within arange in which the dispersibility and the adhesiveness can be obtained.The content of the binder in the silver salt emulsion layer ispreferably ¼ or more, and more preferably ½ or more, in terms of thevolume ratio of silver/binder. The volume ratio of silver/binder ispreferably 100/1 or less, more preferably 50/1 or less, furtherpreferably 10/1 or less, and particularly preferably 6/1 or less.Moreover, the volume ratio of silver/binder is further preferably 1/1 to4/1. The volume ratio of silver/binder is most preferably 1/1 to 3/1. Ifthe volume ratio of silver/binder in the silver salt emulsion layer isset within this range, even in the case where the amount of appliedsilver is adjusted, fluctuations in resistance value can be suppressed,and the conductive sheet for the touch panel having a uniform surfaceresistance can be obtained. Note that the volume ratio of silver/bindercan be obtained by converting the amount of silver halide/the amount ofbinder (weight ratio) in the raw material into the amount of silver/theamount of binder (weight ratio) and further converting the amount ofsilver/the amount of binder (weight ratio) into the amount of silver/theamount of binder (volume ratio).

<Solvent>

The solvent used to form the silver salt emulsion layer is notparticularly limited, and examples thereof include water, organicsolvents (for example, alcohols such as methanol, ketones such asacetone, amides such as formamide, sulfoxides such as dimethylsulfoxide,esters such as ethyl acetate, and ethers), ionic liquids, and a mixturesolvent of these solvents.

The content of the solvent used to form the silver salt emulsion layerof the present embodiment falls within a range of 30 to 90 mass % of thetotal mass of the silver salt, the binder, and the like contained in thesilver salt emulsion layer, and preferably falls within a range of 50 to80 mass % thereof.

<Other Additives>

Various additives used in the present embodiment are not particularlylimited, and known additives can be preferably used therein.

[Other Layer Configurations]

A protective layer (not illustrated) may be provided on the silver saltemulsion layer. The “protective layer” in the present embodiment means alayer made of a binder such as gelatin and polymers, and is formed onthe silver salt emulsion layer having photosensitivity in order toproduce effects of preventing scratches and improving mechanicalcharacteristics. The thickness of the protective layer is preferably 0.5μm or less. A method of applying and a method of forming the protectivelayer are not particularly limited, and a known applying method and aknown forming method can be selected as appropriate. Moreover, forexample, a basecoat layer may also be provided under the silver saltemulsion layer.

Next, steps of the method of manufacturing the conductive sheet 1 aredescribed.

[Exposure to Light]

The present embodiment includes the case where the first electrodepattern 10 and the second electrode pattern 40 are formed by printing.Besides the printing, the first electrode pattern 10 and the secondelectrode pattern 40 are formed by exposure to light, development, andthe like. That is, a photosensitive material having asilver-salt-containing layer or a photosensitive material to whichphotopolymer for photolithography has been applied, which is provided onthe substrate 30, is exposed to light. The exposure to light can beperformed using electromagnetic waves. Examples of the electromagneticwaves include light such as visible light rays and ultraviolet rays andradiant rays such as X-rays. Further, a light source having wavelengthdistribution may be used for the exposure to light, and a light sourcehaving a particular wavelength may be used therefor.

A method using a glass mask and a pattern exposure method using laserdrawing are preferable for the exposure method.

[Development Process]

In the present embodiment, after the emulsion layer is exposed to light,the development process is further performed. A technique of a standarddevelopment process used for silver halide photographic films, printingpaper, printing plate-making films, photomask emulsion masks, and thelike can be used for the development process.

The development process in the present embodiment can include a fixingprocess performed for the purpose of stabilization by removing thesilver salt in the unexposed part. A technique of a fixing process usedfor silver halide photographic films, printing paper, printingplate-making films, photomask emulsion masks, and the like can be usedfor the fixing process in the present invention.

It is preferable that the photosensitive material that has beensubjected to the development and fixing process be subjected to ahardening process, a water washing process, and a stabilization process.

The mass of metal silver contained in the exposed part after thedevelopment process is preferably 50 mass % or more of the mass ofsilver contained in the exposed part before the exposure to light and isfurther preferable 80 mass % or more thereof. If the mass of silvercontained in the exposed part is 50 mass % or more of the mass of silvercontained in the exposed part before the exposure to light, highconductive properties can be obtained, which is preferable.

The gradation after the development process in the present embodiment isnot particularly limited, and preferably exceeds 4.0. If the gradationafter the development process exceeds 4.0, the conductive properties ofthe conductive metal part can be improved while the translucency of thelight transmissive part is kept high. Examples of means for making thegradation 4.0 or more include the doping with rhodium ions and iridiumions described above.

The conductive sheet is obtained through the above-mentioned steps, andthe surface resistance of the obtained conductive sheet is preferably100 Ω/sq. or less, more preferably 80 Ω/sq. or less, further preferably60 Ω/sq. or less, and further more preferably 40 Ω/sq. or less. It isideal to make the lower limit value of the surface resistance as low aspossible. In general, it is sufficient that the lower limit valuethereof be 0.01 Ω/sq. Even 0.1 Ω/sq. or 1 Ω/sq. can be adopted dependingon the purpose of use.

If the surface resistance is adjusted to such a range, positiondetection is possible for even a large-si/e touch panel having an areaof 10 cm×10 cm or more. Moreover, the conductive sheet after thedevelopment process may be further subjected to a calendering process,and the surface resistance can be adjusted to a desired value by thecalendering process.

(Hardening Process after Development Process)

It is preferable to perform a hardening process on the silver saltemulsion layer by immersing the same in a hardener after performing thedevelopment process thereon. Examples of the hardener include:dialdehydes such as glutaraldehyde, adipaldehyde, and2,3-dihydroxy-1,4-dioxane; and inorganic compounds such as boric acidand chrome alum/potassium alum, which are described in Japanese PatentApplication Laid-Open No. 2-14127V.

[Physical Development and Plating Process]

In the present embodiment, physical development and/or a plating processfor causing the metal silver part to support conductive metal grains maybe performed for the purpose of enhancing the conductive properties ofthe metal silver part formed by the exposure to light and thedevelopment process. In the present invention, the metal silver part maybe caused to support conductive metal grains through only any one of thephysical development and the plating process, and the metal silver partmay be caused to support conductive metal grains through a combinationof the physical development and the plating process. Note that the metalsilver part that has been physically developed and/or plated is alsoreferred to as “conductive metal part”.

[Oxidation Process]

In the present embodiment, it is preferable that the metal silver partafter the development process and the conductive metal part formed bythe physical development and/or the plating process be subjected to anoxidation process. For example, in the case where a slight amount ofmetal is deposited in the light transmissive part, the oxidation processcan remove the metal, and can make the transmittance of the lighttransmissive part substantially 100%.

[Light Transmissive Part]

The “light transmissive part” in the present embodiment means atranslucent portion other than the first electrode pattern 10 and thesecond electrode pattern 40, of the conductive sheet 1. As describedabove, the transmittance of the light transmissive part is 90% or more,preferably 95% or more, further preferably 97% or more, further morepreferably 98% or more, and most preferably 99% or more, in terms of thetransmittance indicated by the minimum value of the transmittance in awavelength region of 380 to 780 nm excluding contributions to lightabsorption and reflection of the substrate 30.

[Conductive Sheet 1]

The film thickness of the substrate 30 in the conductive sheet 1according to the present embodiment is preferably 5 to 350 μm andfurther preferably 30 to 150 μm. If the film thickness thereof is setwithin such a range of 5 to 350 μm, a desired transmittance of visiblelight can be obtained, and handling is easy.

The thickness of the metal silver part provided on the substrate 30 canbe determined as appropriate in accordance with the applicationthickness of coating for the silver-salt-containing layer applied ontothe substrate 30. The thickness of the metal silver part can be selectedfrom 0.001 mm to 0.2 mm, and is preferably 30 μm or less, morepreferably 20 μm or less, further preferably 0.01 to 9 μm, and mostpreferably 0.05 to 5 μm. Moreover, it is preferable that the metalsilver part be patterned. The metal silver part may have asingle-layered structure, and may have a multi-layered structure of twoor more layers. In the case where the metal silver part is patterned andhas a multi-layered structure of two or more layers, the metal silverpart can be provided with different color sensitivities so as to bereactive to different wavelengths. As a result, if the metal silver partis exposed to light with different wavelengths, different patterns canbe formed in the respective layers.

For use in a touch panel, a smaller thickness of the conductive metalpart is more preferable, because the viewing angle of a display panel iswider. Also in terms of enhancement in visibility, a reduction inthickness of the conductive metal part is required. From suchperspectives, it is desirable that the thickness of the layer made ofthe conductive metal supported by the conductive metal part be less than9 μm, less than 5 μm, or less than 3 μm, and be 0.1 μm or more.

In the present embodiment, the metal silver part having a desiredthickness can be formed by controlling the application thickness of thesilver-sall-containing layer, and the thickness of the layer made of theconductive metal grains can be freely controlled by the physicaldevelopment and/or the plating process. Hence, even the conductive sheet1 having a thickness that is less than 5 μm and preferably less than 3μm can be easily formed.

Note that the method of manufacturing the conductive sheet according tothe present embodiment does not necessarily need to include the platingstep and the like. This is because the method of manufacturing theconductive sheet 1 according to the present embodiment can obtain adesired surface resistance by adjusting the amount of applied silver andthe volume ratio of silver/binder of the silver salt emulsion layer.

With regard to the above-mentioned manufacturing method, description isgiven of the conductive sheet 1 including: the substrate 30; the firstelectrode pattern 10 formed on the first main surface of the substrate30; and the second electrode pattern 40 formed on the second mainsurface of the substrate 30, which ore illustrated in FIG. 2.Alternatively, as illustrated in FIG. 33, the conductive sheet 1 whichincludes the substrate 30 and the first electrode pattern 10 formed onthe first main surface of the substrate 30, and a conductive sheet 2which includes a substrate 80 and the second electrode pattern 40 formedon a first main surface of the substrate 80 may be placed on top of eachother (overlaid) such that the first electrode pattern 10 and the secondelectrode pattern 40 are orthogonal to each other. The manufacturingmethod applied to the substrate 30 and the first electrode pattern canbe adopted for the substrate 80 and the second electrode pattern 40.

The conductive sheet and the touch panel according to the presentinvention are not limited to the above-mentioned embodiments, and canhave various configurations without departing from the gist of thepresent invention, as a matter of course. Moreover, the conductive sheetand the touch panel according to the present invention can be used inappropriate combination with techniques disclosed in, for example.Japanese Patent Application Laid-Open No. 2011-11314V, No. 2011-129501,No. 2011-129112, No. 2011-13431 Land No. 2011-175028.

Hereinafter, a conductive sheet and a capacitive touch panel accordingto another embodiment are described with reference to FIG. 34 to FIG.40. Note that herein, “to” indicating a numerical value range is used tomean that the numerical value range includes numerical values givenbefore and after “to” as its lower limit value and its upper limitvalue.

As illustrated in FIG. 34 and FIG. 35A, a conductive sheet for a touchpanel (hereinafter, referred to as the conducive sheet 210 for the touchpanel) according to the present embodiment is formed by laminating afirst conductive sheet 212A and a second conductive sheet 212B.

As illustrated in FIG. 34 and FIG. 36, the first conducive sheet 212Aincludes a first electrode pattern 216A formed on one main surface of afirst transparent substrate 214A (see FIG. 35A). The first electrodepattern 216A is formed by a large number of grids made of metal thinwires. The first electrode pattern 216A includes: two or more firstconducts e patterns 218A that extend in a first direction (x direction)and are arranged in a second direction (y direction) orthogonal to thefirst direction; and first nonconductive patterns 220A that electricallyseparate the first conductive patterns 218A from each other. Each firstnonconductive pattern 220A includes a plurality of break parts 222A(referred to as first break parts 222A as needed) formed in portionsother than intersection points of the metal thin wires. The firstconductive patterns 218A are electrically separated from each other bythe plurality of break parts 222A.

The metal thin wires that form the first electrode pattern 216A eachhave a wire width of 0.5 μm to 30 μm. It is desirable that the wirewidth of each metal thin wire be 30 μm or less, preferably 15 μm orless, more preferably 10 μm or less, more preferably 9 μm or less, andmore preferably 7 μm or less, and be preferably 0.5 μm or more. Notethat, although the first conductive patterns 218A and the firstnonconductive patterns 220A have substantially the same wire width, inFIG. 36, in order to clarify the first conductive patterns 218A and thefirst nonconductive patterns 220A, the wire width of each firstconductive pattern 218A is exaggeratingly thickened, and the wire widthof each first nonconductive pattern 220A is exaggeratingly thinned. Thewire width of each first conductive pattern 218A and the wire width ofeach first nonconductive pattern 220A may be the same as each other, andmay be different from each other. Preferably, the wire widths of the twoare the same as each other. The reason for this is that the visibilitymay become lower if the wire widths of the two are different from eachother. The metal thin wires of the first electrode pattern 216A are madeof metal materials such as gold, silver, and copper and conductivematerials such as metal oxides.

The first electrode pattern 216A includes a plurality of grids 224A madeof metal thin wires that intersect with each other. The grids 224A eachinclude an opening region surrounded by the metal thin wires. The grids224A have a grid pitch Pa of 250 μm to 900 μm, and preferably have agrid pitch Pa of 300 μm to 700 μm. The grids 224A of the firstconductive patterns 218A and the grids 224A of the first nonconductivepatterns 220A have substantially the same size.

The grids 224A of the first nonconductive patterns 220A include thebreak parts 222A in portions other than the intersection parts of themetal thin wires. All the grids 224A that form the first nonconductivepatterns 220A do not necessarily need to include the break parts 222A.It is sufficient that the first nonconductive patterns 220A can achieveelectrical separation between adjacent ones of the first conductivepatterns 218A. The length of each break part 222A is preferably 60 μm orless, and is more preferably 10 to 50 μm, 15 to 40 μm, and 20 to 40 μm.Moreover, the formation range of the break ports 222A can be expressedby, for example, a fluctuation in wire density. Here, the fluctuation inwire density refers to a fluctuation in total thin wire length of unitsmall grids, and can be defined as ±(the maximum value of total wirelength−the minimum value of total wire length)/the average value oftotal wire length/2(%). The formation range of the break parts 222A ispreferably ±15%, more preferably ±10%, and further preferably ±0.5% to±5%, in terms of the fluctuation in wire density.

In the conductive sheet 210 for the touch panel, each grid 224A has asubstantially rhomboid shape. Here, the substantially rhomboid shapemeans a parallelogram whose diagonals are substantially orthogonal toeach other. Alternatively, each grid 224A may have other polygonalshapes. Moreover, the shape of one side of each grid 224A may be acurved shape or a circular arc shape instead of a straight shape. In thecase of the circular arc shape, for example, opposing two of the sidesof each grid 224A may each have a circular arc shape convex outward, andother opposing two of the sides thereof may each have a circular arcshape convex inward. Moreover, the shape of each side of each grid 224Amay be a wavy shape in which a circular arc convex outward and acircular arc convex inward are alternately continuous. As a matter ofcourse, the shape of each side thereof may be a sine curve.

Each first conductive pattern 218A includes wider portions and narrowerportions that are alternately placed along the first direction (xdirection). Similarly, each first nonconductive pattern 220A includeswider portions and narrower portions that are alternately placed alongthe first direction (x direction). The order of the wider portions andthe narrower portions of each first conductive pattern 218A is oppositeto the order of the wider portions and the narrower portions of eachfirst nonconductive pattern 220A.

Each first conductive pattern 218A has one end electrically connected toa first external wire 262A via a first terminal 260A. Meanwhile, eachfirst conductive pattern 218A has another end that is an opened end.

As illustrated in FIG. 34 and FIG. 37, the second conductive sheet 212Bincludes a second electrode pattern 216B formed on one main surface of asecond transparent substrate 214B (see FIG. 35A). The second electrodepattern 216B is formed by a large number of grids made of metal thinwires. The second electrode pattern 216B includes: two or more secondconductive patterns 218B that extend in the second direction (vdirection) and are arranged in the first direction (x direction)orthogonal to the second direction; and second nonconductive patterns220B that electrically separate the second conductive patterns 218B fromeach other. Each second nonconductive pattern 220B includes a pluralityof break parts 222B (referred to as second break parts 222B as needed)formed in portions other than intersection points of the metal thinwires. The second conductive patterns 218B are electrically separatedfrom each other by the plurality of break parts 222B.

The metal thin wires that form the second electrode pattern 216B eachhave a wire width of 0.5 μm to 30 μm. It is desirable that the wirewidth of each metal thin wire be 30 μm or less, preferably 15 μm orless, more preferably 10 μm or less, more preferably 9 μm or less, andmore preferably 7 μm or less, and be preferably 0.5 μm or more. Notethat, although the second conductive patterns 218B and the secondnonconductive patterns 220B have substantially the same wire width, inFIG. 37, in order to clarify the second conductive patterns 218B and thesecond nonconductive patterns 220B, the wire width of each secondconductive pattern 218B is exaggeratingly thickened, and the wire widthof each second nonconductive pattern 220B is exaggeratingly thinned. Thewire width of each second conductive pattern 218B and the wire width ofeach second nonconductive pattern 220B may be the same as each other,and may be different from each other. Preferably, the wire widths of thetwo are the same as each other. The reason for this is that thevisibility may become lower if the wire widths of the two are differentfrom each other. The metal thin wires of the second electrode pattern216B are made of metal materials such as gold, silver, and copper andconductive materials such as metal oxides.

The second electrode pattern 216B includes a plurality of grids 224Bmade of metal thin wires that intersect with each other. The grids 224Beach include an opening region surrounded by the metal thin wires. Thegrids 224B have a grid pitch Pb of 250 μm to 900 μm, and preferably havea grid pitch Pb of 300 μm to 700 μm. The grids 224B of the secondconductive patterns 218B and the grids 224B of the second nonconductivepatterns 220B have substantially the same size.

The grids 224B of the second nonconductive patterns 220B include thebreak parts 222B in portions other than the intersection parts of themetal thin wires. All the grids 224B that form the second nonconductivepatterns 220B do not necessarily need to include the break parts 222B.It is sufficient that the second nonconductive patterns 220B can achieveelectrical separation between adjacent ones of the second conductivepatterns 218B. The length of each break part 222B is preferably 60 μm orless, and is more preferably 10 to 50 μm, 15 to 40 μm, and 20 to 40 μm.Moreover, the formation range of the break parts 222B can be expressedby, for example, a fluctuation in wire density. Here, the fluctuation inwire density refers to a fluctuation in total thin wire length of unitsmall grids, and can be defined as ±(the maximum value of total wirelength−the minimum value of total wire length)/the average value oftotal wire length/2(%). The formation range of the break parts 222B ispreferably ±15%, more preferably ±10%, and further preferably ±0.5% to±5%, in terms of the fluctuation in wire density.

In the conductive sheet 210 for the touch panel, each grid 224B has asubstantially rhomboid shape. Here, the substantially rhomboid shapemeans a parallelogram whose diagonals are substantially orthogonal toeach other. Alternatively, each grid 224B may have other polygonalshapes. Moreover, the shape of one side of each grid 224B may be acurved shape or a circular arc shape instead of a straight shape. In thecase of the circular arc shape, for example, opposing two of the sidesof each grid 224B may each have a circular arc shape convex outward, andother opposing two of the sides thereof may each have a circular arcshape corn ex inward. Moreover, the shape of each side of each grid 224Bmay be a waxy shape in which a circular arc convex outward and acircular arc convex inward are alternately continuous. As a matter ofcourse, the shape of each side thereof may be a sine curve.

Each second conductive pattern 218B includes wider portions and narrowerportions that are alternately placed along the second direction (ydirection). Similarly, each second nonconductive pattern 220B includeswider portions and narrower portions that ore alternately placed alongthe second direction (y direction). The order of the wider portions andthe narrower portions of each second conductive pattern 218B is oppositeto the order of the wider portions and the narrower portions of eachsecond nonconductive pattern 220B.

Each second conductive pattern 218B has one end electrically connectedto a second external wire 262B via a second terminal 260B. Meanwhile,each second conductive pattern 218B has another end that is an openedend.

Then, when the conductive sheet 210 for the touch panel is formed bylaminating, for example, the first conductive sheet 212A on the secondconductive sheet 212B, the first electrode pattern 216A and the secondelectrode pattern 216B are placed so as not to overlap with each otheras illustrated in FIG. 38. At this lime, the first electrode pattern216A and the second electrode pattern 216B are placed such that thenarrower portions of the first conductive patterns 218A are opposed tothe narrower portions of the second conductive patterns 218B and thatthe narrower portions of the first conductive patterns 218A intersectwith the narrower portions of the second conductive patterns 218B. As aresult, the first electrode pattern 216A and the second electrodepattern 216B form a combination pattern 270. Note that the wire widthsof the first electrode pattern 216A and the second electrode pattern216B are substantially the same as each other. Moreover, the sizes ofthe grids 224A and the grids 224B are substantially the same as eachother. However, in FIG. 38, in order to clarify a positional relation ofthe first electrode pattern 216A and the second electrode pattern 216B,the wire width of the first electrode pattern 216A is made thicker thanthe wire width of the second electrode pattern 216B.

In the combination pattern 270, the grids 224A and the grids 224B formsmall grids 276 in top view. That is, the intersection parts of thegrids 224A are respectively placed in the opening regions of the grids224B. Note that the small grids 276 have a grid pitch Ps of 125 μm to450 μm that is half the respective grid pitches Pa and Pb of the grids224A and the grids 224B, and preferably have a grid pitch Ps of 150 μmto 350 μm.

The break parts 222A of the first nonconductive patterns 220A are formedin portions other than the intersection parts of the grids 224A, and thebreak parts 222B of the second nonconductive patterns 220B are formed inportions other than the intersection parts of the grids 224B. As aresult, a decrease in visibility caused by the break parts 222A and thebreak parts 222B can be prevented in the combination pattern 270.

In particular, the metal thin wires of the second conductive patterns218B are placed at positions opposed to the break parts 222A. Moreover,the metal thin wires of the first conductive patterns 218A are placed atpositions opposed to the break parts 222B. The metal thin wires of thesecond conductive patterns 218B mask the break parts 222A, and the metalthin wires of the first conductive patterns 218A mask the break parts222B. Accordingly, in the combination pattern 270, the break parts 222Aand the break parts 222B are less easily visually observed in top view,and hence the visibility can be enhanced. In consideration ofenhancement in visibility, it is preferable that the length of eachbreak part 222A and the wire width of each of the metal thin wires ofthe second conductive patterns 218B satisfy a relational expression ofthe wire width×1<the break part<the wire width×10. Similarly, it ispreferable that the length of each break part 222B and the wire width ofeach of the metal thin wires of the first conductive patterns 218Asatisfy a relational expression of the wire width×1<the break part<thewire width×10.

Next, a relation between the second break parts 222B and the metal thinwires of the first conductive patterns 218A and a relation between thefirst break parts 222A and the metal thin wires of the second conductivepatterns 218B are described. FIG. 39 is a schematic view illustrating apositional relation between the metal thin wire and the break part.Assuming that the width of each of the metal thin wires of the firstconductive patterns 218A and the metal thin wires of the secondconductive patterns 218B is a and that the width of each of the firstbreak parts 222A of the first nonconductive patterns 220A and the secondbreak parts 222B of the second nonconductive patterns 220B is b, it ispreferable that a relational expression of b−a≤30 μm be satisfied. Thismeans that, as a difference between the width of each metal thin wireand the width of each break part is smaller, a portion of the break partoccupied by the metal thin wire is larger, and a decrease in visibilitycan be more prevented.

Moreover, assuming that the width of each of the metal thin wires of thefirst conductive patterns 218A and the metal thin wires of the secondconductive patterns 218B is a and that the width of each of the firstbreak parts 222A of the first nonconductive patterns 220A and the secondbreak parts 222B of the second nonconductive patterns 220B is b, it ispreferable that a relational expression of (b−a)/a≤6 be satisfied. Thismeans that the width of each of the second break parts 222B of thesecond nonconductive patterns 220B is equal to or less than apredetermined width, with respect to the width of each of the metal thinwires of the first conductive patterns 218A and the metal thin wires ofthe second conductive patterns 218B. Similarly to the above, this meansthat a portion of each break part occupied by each metal thin wire is aslarge as possible, and a decrease in visibility can be more prevented.

Next, a positional misalignment between the central position of eachmetal thin wire and the central position of each break part isdescribed. FIG. 40 is a schematic view illustrating a relation betweenthe central position of the metal thin wire and the central position ofthe break pan. A central line CL1 designates the central position ofeach of the metal thin wires of the first conductive patterns 218A andthe metal thin wires of the second conductive patterns 218B. A centralline CL2 designates the central position of each of the second breakparts 222B and the first break parts 222A. An amount of misalignment dmeans a distance between the central line CL1 and the central line CL2.Assuming that each amount of misalignment is d and that the averagevalue of the amounts of misalignment d is dAve, it is preferable that astandard deviation σ be 10 μm or less. A small standard deviation σmeans that fluctuations in the amount of misalignment d between thecentral line CL1 and the central line CL2 are small. In the case whereeach metal thin wire is located as closer to the center of each breakpart as possible, distances L1 and L2 that are gaps between the metalthin wires of the first conductive patterns 218A and the metal thinwires of the second nonconductive patterns 220B are more equal to eachother, or distances L1 and L2 that are gaps between the metal thin wiresof the second conductive patterns 218B and the metal thin wires of thefirst nonconductive patterns 220A are more equal to each other. Suchsymmetry makes the patterns less perceivable in terms of humanvisibility, with the result that a decrease in visibility can beprevented.

In the case where the conductive sheet 210 for the touch panel is usedfor a touch panel, a protective layer (not illustrated) is formed on thefirst conductive sheet 212A. The first external wires 262A respectivelydrawn from the large number of first conductive patterns 218A of thefirst conductive sheet 212A and the second external wires 262Brespectively drawn from the large number of second conductive patterns218B of the second conductive sheet 212B are connected to, for example,an 1C circuit that controls scanning.

In order to minimize the area of a peripheral region outside of adisplay screen of a liquid crystal display device, of the conductivesheet 210 for the touch panel, preferably, the respective connectionparts between the first conductive patterns 218A and the first externalwires 262A are linearly arranged, and the respective connection partsbetween the second conductive patterns 218B and the second externalwires 262B are linearly arranged.

If the tip of a finger is brought into contact with the protectivelayer, an electrostatic capacitance between the first conductivepatterns 218A and the second conductive patterns 218B opposed to the tipof the finger changes. The 1C circuit detects the amount of this change,and calculates the position of the tip of the finger on the basis of theamount of this change. Such calculation is performed on between eachfirst conductive pattern 218A and each second conductive pattern 218B.Accordingly, even if the tips of two or more fingers are brought intocontact at the same time, the position of the tip of each finger can bedetected.

In this way, in the case where the conductive sheet 210 for the touchpanel is applied to, for example, a projected capacitive touch panel,the conductive sheet 210 for the touch panel can increase a responsespeed because of its small surface resistance, and can promote anincrease in size of the touch panel.

Next, a method of manufacturing the first conductive sheet 212A and thesecond conductive sheet 212B is described.

In the case of manufacturing the first conductive sheet 212A and thesecond conductive sheet 212B, for example, a photosensitive materialhaving an emulsion layer containing photosensitive silver halide isexposed to light and developed on each of the first transparentsubstrate 214A and the second transparent substrate 214B, and a metalsilver part (metal thin wires) and a light transmissive part (openingregions) are respectively formed in the exposed part and the unexposedpart, whereby the first electrode pattern 216A and the second electrodepattern 216B may be formed. Note that the metal silver part is furtherphysically developed and/or plated, whereby the metal silver part may becaused to support conductive metal.

Alternatively, a resist pattern is formed by exposing to light anddeveloping a photoresist film on copper foil formed on each of the firsttransparent substrate 214A and the second transparent substrate 214B,and the copper foil exposed on the resist pattern is etched, whereby thefirst electrode pattern 216A and the second electrode pattern 216B maybe formed.

Alternatively, a paste containing metal fine grains is printed on eachof the first transparent substrate 214A and the second transparentsubstrate 214B, and the paste is plated with metal, whereby the firstelectrode pattern 216A and the second electrode pattern 216B may beformed.

The first electrode pattern 216A and the second electrode pattern 216Bmay be respectively formed by printing on the first transparentsubstrate 214A and the second transparent substrate 214B, using a screenprinting plate or a gravure printing plate. Alternatively, the firstelectrode pattern 216A and the second electrode pattern 216B may berespectively formed on the first transparent substrate 214A and thesecond transparent substrate 214B, according to an inkjet process.

In a case as illustrated in FIG. 35B where the first electrode pattern216A is formed on one main surface of the first transparent substrate214A and where the second electrode pattern 216B is formed on anothermain surface of the first transparent substrate 214A, if a standardmanufacturing method (in which the one main surface is first exposed tolight, and the another main surface is then exposed to light) isadopted, the first electrode pattern 216A and the second electrodepattern 216B having desired patterns cannot be obtained in some cases.

In view of the above, the following manufacturing method can bepreferably adopted.

That is, photosensitive silver halide emulsion layers respectivelyformed on both the surfaces of the first transparent substrate 214A arecollectively exposed to light, whereby the first electrode pattern 216Ais formed on the one main surface of the first transparent substrate214A while the second electrode pattern 216B is formed on the anothermain surface of the first transparent substrate 214A.

A specific example of the method of manufacturing the conductive sheetaccording to aspects illustrated in FIGS. 34 to 40 is described.

First, an elongated photosensitive material is manufactured. Thephotosensitive material includes: the first transparent substrate 214A;a photosensitive silver halide emulsion layer (hereinafter, referred toas first photosensitive layer) formed on the one main surface of thefirst transparent substrate 214A; and a photosensitive silver halideemulsion layer (hereinafter, referred to as second photosensitive layer)formed on the another main surface of the first transparent substrate214A.

Subsequently, the photosensitive material is exposed to light. Thisexposure process includes: a first exposure process performed on thefirst photosensitive layer, in which the first transparent substrate214A is irradiated with light so that the first photosensitive layer isexposed to the light along a first exposure pattern; and a secondexposure process performed on the second photosensitive layer, in whichthe first transparent substrate 214A is irradiated with light so thatthe second photosensitive layer is exposed to the light along a secondexposure pattern (both-surfaces simultaneous exposure).

For example, in the slate where the elongated photosensitive material istransported in one direction, the first photosensitive layer isirradiated with first light (parallel light) with the intermediation ofa first photomask, while the second photosensitive layer is irradiatedwith second light (parallel light) with the intermediation of a secondphotomask. The first light is obtained by converting, into parallellight, light emitted from a first light source by means of a halfwayfirst collimator lens. The second light is obtained by converting, intoparallel light, light emitted from a second light source by means of ahalfway second collimator lens.

Although description is given above of the case where the two lightsources (the first light source and the second light source) are used,light emitted from one light source may be split by an optical systeminto the first light and the second light, and the first photosensitivelayer and the second photosensitive layer min be irradiated with thefirst light and the second light.

Subsequently, the photosensitive material after the exposure to light isdeveloped, whereby, for example, the conductive sheet 210 for the touchpanel as illustrated in FIG. 35B is made. The conductive sheet 210 forthe touch panel includes: the first transparent substrate 214A; thefirst electrode pattern 216A that is formed along the first exposurepattern on the one main surface of the first transparent substrate 214A;and the second electrode pattern 216B that is formed along the secondexposure pattern on the another main surface of the first transparentsubstrate 214A. Note that the exposure time and the development lime ofthe first photosensitive layer and the second photosensitive layer mayvariously change depending on the types of the first light source andthe second light source, the type of a developing solution, and thelike. Hence preferable numerical value ranges therefor cannot beunconditionally determined, but the exposure time and the developmenttime are adjusted such that the development rate is 100%.

Then, according to the manufacturing method of the present embodiment,in the first exposure process, the first photomask is, for example,closely placed on the first photosensitive layer, and is irradiated withthe first light emitted from the first light source that is placed so asto be opposed to the first photomask, whereby the first photosensitivelayer is exposed to light. The first photomask includes a glasssubstrate made of transparent soda glass and a mask pattern (firstexposure pattern) formed on the glass substrate. Accordingly, in thefirst exposure process, a portion of the first photosensitive layer isexposed to light, the portion being along the first exposure patternformed on the first photomask. A gap of approximately 2 to 10 μm may beprovided between the first photosensitive layer and the first photomask.

Similarly, in the second exposure process, the second photomask is, forexample, closely placed on the second photosensitive layer, and isirradiated with the second light emitted from the second light sourcethat is placed so as to be opposed to the second photomask, whereby thesecond photosensitive layer is exposed to light. Similarly to the firstphotomask, the second photomask includes a glass substrate made oftransparent soda glass and a mask pattern (second exposure pattern)formed on the glass substrate. Accordingly, in the second exposureprocess, a portion of the second photosensitive layer is exposed tolight, the portion being along the second exposure pattern formed on thesecond photomask. In this case, a gap of approximately 2 to 10 μm may beprovided between the second photosensitive layer and the secondphotomask.

In the first exposure process and the second exposure process, theemission timing of the first light from the first light source and theemission timing of the second light from the second light source may bethe same as each other, and may be different from each other. If theemission timings thereof are the same as each other, the firstphotosensitive layer and the second photosensitive layer can besimultaneously exposed to light in one exposure process, and theprocessing time can be shortened. Meanwhile, in the case where both thefirst photosensitive layer and the second photosensitive layer are notspectrally sensitized, if the photosensitive material is exposed tolight on both the sides thereof, the exposure to light on one sideinfluences image formation on the other side (rear side).

That is, the first light from the first light source that has reachedthe first photosensitive layer is scattered by silver halide grainscontained in the first photosensitive layer, and is transmitted asscattered light through the first transparent substrate 214A, and partof the scattered light reaches even the second photosensitive layer.Consequently, a boundary portion between the second photosensitive layerand the first transparent substrate 214A is exposed to the light over awide range, so that a latent image is formed. Hence, the secondphotosensitive layer is exposed to both the second light from the secondlight source and the first light from the first light source. In thecase of manufacturing the conductive sheet 210 for the touch panel inthe subsequent development process, a thin conductive layer based on thefirst light from the first light source is formed between the conductivepatterns in addition to the conductive pattern (second electrode pattern216B) along the second exposure pattern, and a desired pattern (apattern along the second exposure pattern) cannot be obtained. The sameapplies to the first photosensitive layer.

As a result of intensive studies for avoiding this, the presentinventors find out the following point. That is, if the thickness ofeach of the first photosensitive layer and the second photosensitivelayer is set within a particular range or if the amount of silverapplied to each of the first photosensitive layer and the secondphotosensitive layer is specified, silver halide itself absorbs light,and this can restrict light transmission to the rear surface. In thepresent embodiment, the thickness of each of the first photosensitivelayer and the second photosensitive layer can be set to 1 μm or more and4 μm or less. The upper limit value thereof is preferably 2.5 μm.Moreover, the amount of silver applied to each of the firstphotosensitive layer and the second photosensitive layer is specified to5 to 20 g/m².

In the above-mentioned exposure method of both-surfaces close contacttype, an image defect due to a hindrance to exposure by dust and thelike attached to the sheet surface is problematic. In order to preventsuch dust attachment, it is known to apply a conductive substance to thesheet, but metal oxides and the like remain even after the process toimpair the transparency of a final product, and conductive polymers havea problem in preserving properties. As a result of intensive studies inview of the above, the present inventors find out that conductiveproperties necessary for prevention of static charge can be obtained bysilver halide with a reduced binder, and thus specify the volume ratioof silver/binder of each of the first photosensitive layer and thesecond photosensitive layer. That is, the volume ratio of silver/binderof each of the first photosensitive layer and the second photosensitivelayer is 1/1 or more, and is preferably 2/1 or more.

If the thickness, the amount of applied silver, and the volume ratio ofsilver/binder of each of the first photosensitive layer and the secondphotosensitive layer are set and specified as described above, the firstlight from the first light source that has reached the firstphotosensitive layer does not reach the second photosensitive layer.Similarly, the second light from the second light source that hasreached the second photosensitive layer does not reach the firstphotosensitive layer. As a result in the case of manufacturing theconductive sheet 210 for the touch panel in the subsequent developmentprocess, as illustrated in FIG. 35B, only the first electrode pattern216A along the first exposure pattern is formed on the one main surfaceof the first transparent substrate 214A, and only the second electrodepattern 216B along the second exposure pattern is formed on the anothersurface of the first transparent substrate 214A, so that desiredpatterns can be obtained.

In this way, according to the above-mentioned manufacturing method usingboth-surfaces collective exposure, the first photosensitive layer andthe second photosensitive layer having both conductive properties andsuitability for the both-surfaces exposure can be obtained. Moreover,the same pattern or different patterns can be arbitrarily formed on boththe surfaces of the first transparent substrate 214A in one exposureprocess on the first transparent substrate 214A. This can facilitateformation of the electrodes of the touch panel, and can achieve areduction in thickness (a reduction in height) of the touch panel.

Next, focused description is given of a method of using a silver halidephotographic photosensitive material corresponding to a particularlypreferable aspect, for the first conducive sheet 212A and the secondconductive sheet 212B according to the present embodiment.

The method of manufacturing the first conducive sheet 212A and thesecond conductive sheet 212B according to the present embodimentincludes the following three aspects depending on modes of thephotosensitive material and the development process.

(1) An aspect in which: a silver halide black-and-white photosensitivematerial not including the center of physical development is chemicallydeveloped or thermally developed; and a metal silver part is formed onthe photosensitive material.

(2) An aspect in which: a silver halide black-and-white photosensitivematerial including the center of physical development in a silver halideemulsion layer is dissolved and physically developed; and a metal silverpart is formed on the photosensitive material.

(3) An aspect in which: a silver halide black-and-white photosensitivematerial not including the center of physical development and an imagereceiving sheet having a non-photosensitive layer including the centerof physical development are put on top of each other (overlaid) and thensubjected to diffusion transfer development; and a metal silver part isformed on the non-photosensitive image receiving sheet.

According to the aspect in (1), which is of integrated black-and-whitedevelopment type, a translucent conductive film such as alight-transmissive conductive film is formed on the photosensitivematerial. The obtained developed silver is chemically developed silveror thermally developed silver, and is highly active in the subsequentplating or physical development process, because the obtained developedsilver is a filament having a high-specific surface.

According to the aspect in (2), in the exposed part, silver halidegrains near the center of physical development are dissolved anddeposited on the center of development, whereby a translucent conductivefilm such as a light-transmissive conductive film is formed on thephotosensitive material. This aspect is also of integratedblack-and-white development type. Because the development action isdeposition on the center of physical development, high activity isobtained, and the developed silver has a spherical shape with asmall-specific surface.

According to the aspect in (3), in the unexposed part, silver halidegrains are dissolved and diffused to be deposited on the center ofdevelopment on the image receiving sheet, whereby a translucentconductive film such as a light-transmissive conductive film is formedon the image receiving sheet. This aspect is of so-called separate type,in which the image receiving sheet is separated for use from thephotosensitive material.

In any one of these aspects, both a negative development process and areversal development process can be selected (in the case of a diffusiontransfer method, the use of an auto-positive photosensitive material asthe photosensitive material enables the negative development process).

The chemical development, the thermal development, the dissolution andphysical development, and the diffusion transfer development describedabove have the same meanings as those of the respective terms normallyused in this technical field, and are explained in general textbooksabout photographic chemistry, for example, “Shashin Kagaku (PhotographicChemistry)” written by Shinichi Kikuchi (published by Kyoritsu ShuppanCo., Ltd. in 1955) and “The Theory of Photographic Processes, 4th ed.”edited by C. E. K. Mees (published by Mcmillan Publishers Ltd in 1977).Although description is given above of an invention relating to liquidprocesses, but techniques adopting thermal development methods can alsobe referred to as other development methods. For example, it is possibleto apply techniques described in Japanese Patent Application Laid-OpenNo. 2004-184693, No. 2004-334077, and No. 2005-010752 and JapanesePatent Application No. 2004-244080 and No. 2004-085655.

Here, layer configurations of the first conductive sheet 212A and thesecond conductive sheet 212B according to the present embodiment oredescribed below in detail.

[First Transparent Substrate 214A and Second Transparent Substrate 214B]

The first transparent substrate 214A and the second transparentsubstrate 214B can be each formed using a plastic film, a plastic plate,a glass plate, and the like.

Examples of the raw materials of the plastic film and the plastic plateinclude: polyesters such as polyethylene terephthalate (PET) andpolyethylene naphthalate (PEN); polyolefins such as polyethylene (PE),polypropylene (PP), polystyrene, and ethylene vinyl acetate(EVA)/cycloolefin polymer (COP)/cycloolefin copolymer (COC); vinylresins; polycarbonate (PC); polyamide; polyimide; acrylic resins; andtriacetylcellulose (TAC).

It is preferable that the first transparent substrate 214A and thesecond transparent substrate 214B be each formed using a plastic film ora plastic plate made of PET (melting point: 258° C.). PEN (meltingpoint: 26V° C.). PE (melting point: 135° C.). PP (melting point: 163°C.), polystyrene (melting point: 230° C.), polyvinyl chloride (meltingpoint: 180° C.), polyvinylidene chloride (melting point: 212° C.), orTAC (melting point: 290° C.) having a melting point of about 290° C. orless. In particular. PET is preferable from the perspective of the lighttransmissivity, the workability, and the like. Because transparentconductive films such as the first conductive sheet 212A and the secondconductive sheet 212B used in the conductive sheet 210 for the touchpanel are required to have transparency, it is preferable that thedegree of transparency of each of the first transparent substrate 214Aand the second transparent substrate 214B be high.

[Silver Salt Emulsion Layer]

A silver salt emulsion layer that becomes each of the first electrodepattern 216A of the first conductive sheet 212A and the second electrodepattern 216B of the second conductive sheet 212B contains additives suchas a solvent and a colorant in addition to a silver salt and a binder.

Examples of the silver salt used in the present embodiment includeinorganic silver salts such as silver halide and organic silver saltssuch as silver acetate. In the present embodiment, it is preferable touse silver halide excellent in characteristics as an optical sensor.

The amount of silver (the amount of silver salt) applied to the silversalt emulsion layer is preferably 1 to 30 g/m², more preferably 1 to 25g/m², and further preferably 5 to 20 g/m², in terms of silver. If theamount of applied silver is set within this range, a desired surfaceresistance can be obtained in the case of manufacturing the conductivesheet 210 for the touch panel.

Examples of the binder used in the present embodiment include gelatin,polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), polysaccharidessuch as starch, cellulose and derivatives thereof, polyethylene oxide,polyvinylamine, chitosan, polylysine, polyacrylic acid, polyalginicacid, polyhyaluronic acid, and carboxycellulose. These substances eachexhibit a neutral, anionic, or cationic property depending on theionicity of a functional group thereof.

The content of the binder in the silver salt emulsion layer in thepresent embodiment is not particularly limited, and can be determined asappropriate within a range in which the dispersibility and theadhesiveness can be obtained. The content of the binder in the silversalt emulsion layer is preferably ¼ or more, and more preferably ½ ormore, in terms of the volume ratio of silver/binder. The volume ratio ofsilver/binder is preferably 100/1 or less, more preferably 50/1 or less.Moreover, the volume ratio of silver/binder is further preferably 1/1 to4/1. The volume ratio of silver/binder is most preferably 1/1 to 3/1. Ifthe volume ratio of silver/binder in the silver salt emulsion layer isset within this range, even in the case where the amount of appliedsilver is adjusted, fluctuations in resistance value can be suppressed,and the conductive sheet for the touch panel having a uniform surfaceresistance can be obtained. Note that the volume ratio of silver/bindercan be obtained by converting the amount of silver halide/the amount ofbinder (weight ratio) in the raw material into the amount of silver/theamount of binder (weight ratio) and further converting the amount ofsilver/the amount of binder (weight ratio) into the amount of silver/theamount of binder (volume ratio).

<Solvent>

The solvent used to form the silver salt emulsion layer is notparticularly limited, and examples thereof include water, organicsolvents (for example, alcohols such as methanol, ketones such asacetone, amides such as formamide, sulfoxides such as dimethylsulfoxide,esters such as ethyl acetate, and ethers), ionic liquids, and a mixturesolvent of these solvents.

The content of the solvent used to form the silver salt emulsion layerof the present embodiment falls within a range of 30 to 90 mass % of thetotal mass of the silver salt, the binder, and the like contained in thesilver salt emulsion layer, and preferably falls within a range of 50 to80 mass % thereof.

<Other Additives>

Various additives used in the present embodiment are not particularlylimited, and known additives can be preferably used therein.

[Other Layer Configurations]

A protective layer (not illustrated) may be provided on the silver saltemulsion layer. The “protective layer” in the present embodiment means alayer made of a binder such as gelatin and polymers, and is formed onthe silver salt emulsion layer having photosensitivity in order toproduce effects of preventing scratches and improving mechanicalcharacteristics. The thickness of the protective layer is preferably 0.5μm or less. A method of applying and a method of forming the protectivelayer are not particularly limited, and a known apply ing method and aknown forming method can be selected as appropriate. Moreover, forexample, a basecoat layer may also be provided under the silver saltemulsion layer.

Next, steps of the method of manufacturing the first conductive sheet212A and the second conductive sheet 212B are described.

[Exposure to Light]

The present embodiment includes the case where the first electrodepattern 216A and the second electrode pattern 216B are formed byprinting. Besides the printing, the first electrode pattern 216A and thesecond electrode pattern 216B are formed by exposure to light,development, and the like. That is, a photosensitive material having asilver-salt-containing layer or a photosensitive material to whichphotopolymer for photolithography has been applied, which is provided oneach of the first transparent substrate 214A and the second transparentsubstrate 214B, is exposed to light. The exposure to light can beperformed using electromagnetic waves. Examples of the electromagneticwaves include light such as visible light rays and ultraviolet rays andradiant rays such as X-rays. Further, a light source having wavelengthdistribution may be used for the exposure to light, and a light sourcehaving a particular wavelength may be used therefor.

A method using a glass mask and a pattern exposure method using laserdrawing are preferable for the exposure method.

[Development Process]

In the present embodiment, after the emulsion layer is exposed to light,the development process is further performed. A technique of a standarddevelopment process used for silver halide photographic films, printingpaper, printing plate-making films, photomask emulsion masks, and thelike can be used for the development process. The developing solution isnot particularly limited, and a PQ developing solution, an MQ developingsolution, an MAA developing solution, and the like can be used therefor.Examples of the usable developing solutions include: CN-16, CR-56,CP45X, FD-3, and Papitol (produced by Fujifilm Corporation); C-41, E-6,RA-4, D-19, and D-72 (produced by Kodak Company); and developingsolutions included in kits thereof, which are commercially available.Moreover, a lith-developing solution can also be used.

The development process in the present embodiment can include a fixingprocess performed for the purpose of stabilization by removing thesilver salt in the unexposed part. A technique of a fixing process usedfor silver halide photographic films, printing paper, printingplate-making films, photomask emulsion masks, and the like can be usedfor the fixing process in the present invention.

The fixing temperature in the fixing process is preferably about 20° C.to about 50° C. and further preferably 25° C. to 45° C. Moreover, thefixing lime is preferably 5 seconds to 1 minute and further preferably 7seconds to 50 seconds. The replenisher rate of the fixing solution ispreferably 600 ml/m² or less, further preferably 500 ml/m² or less, andparticularly preferably 300 ml/m² or less, with respect to theprocessing amount of the photosensitive material.

It is preferable that the photosensitive material that has beensubjected to the development and fixing process be subjected to a waterwashing process and a stabilization process. The water washing processor the stabilization process is normally performed at a washing wateramount of 20 liters or less, and can be performed even at a replenisherrate of 3 liters or less (including 0, that is, stored water washing),per square meter of the photosensitive material.

The mass of metal silver contained in the exposed part after thedevelopment process is preferably 50 mass % or more of the mass ofsilver contained in the exposed part before the exposure to light, andis further preferable 80 mass % or more thereof. If the mass of silvercontained in the exposed part is 50 mass % or more of the mass of silvercontained in the exposed part before the exposure to light, highconductive properties can be obtained, which is preferable.

The gradation after the development process in the present embodiment isnot particularly limited, and preferably exceeds 4.0. If the gradationafter the development process exceeds 40, the conductive properties ofthe conductive metal part can be improved while the translucency of thelight transmissive part is kept high. Examples of means for making thegradation 4.0 or more include the doping with rhodium ions and iridiumions described above.

The conductive sheet is obtained through the above-mentioned steps, andthe surface resistance of the obtained conductive sheet is preferably100 Ω/sq. or less, preferably falls within a range of 0.1 to 100 Ω/sq.,and more preferably falls within a range of 1 to 10 Ω/sq. If the surfaceresistance is adjusted to such a range, position detection is possiblefor even a large-size touch panel having an area of 10 cm×10 cm or more.Moreover, the conductive sheet after the development process may befurther subjected to a calendering process, and the surface resistancecan be adjusted to a desired value by the calendering process.

[Physical Development and Plating Process]

In the present embodiment, physical development and/or a plating processfor causing the metal silver part to support conductive metal grains maybe performed for the purpose of enhancing the conductive properties ofthe metal silver part formed by the exposure to light and thedevelopment process. In the present invention, the metal silver part maybe caused to support conductive metal grains through only any one of thephysical development and the plating process, and the metal stiver partmay be caused to support conductive metal grains through a combinationof the physical development and the plating process. Note that the metalsilver part that has been physically developed and/or plated is alsoreferred to as “conductive metal part”.

[Oxidation Process]

In the present embodiment, it is preferable that the metal silver partafter the development process and the conductive metal part formed bythe physical development and/or the plating process be subjected to anoxidation process. For example, in the case where a slight amount ofmetal is deposited in the light transmissive part, the oxidation processcan remove the metal, and can make the transmittance of the lighttransmissive part substantially 100%.

[Electrode Patterns]

The wire width of each of the metal thin wires of the first electrodepattern 216A and the second electrode pattern 216B of the presentembodiment can be selected from 30 μm or less. For use in the materialof the touch panel, the metal thin wires each have a wire width of 0.5μm to 30 μm. It is desirable that the wire width of each metal thin wirebe 30 μm or less, preferably 15 μm or less, more preferably 10 μm orless, more preferably 9 μm or less, and more preferably 7 μm or less,and be preferably 0.5 μm or more.

The wire interval (grid pitch) is preferably 250 μm to 900 μm, and isfurther preferably 300 μm or more and 700 μm or less. Moreover, eachmetal thin wire may have a portion wider than 200 μm, for the purpose ofground connection and other purposes.

In the electrode patterns of the present embodiment, the opening ratiois preferably 85% or more, further preferably 90% or more, and mostpreferably 95% or more, in terms of the visible light transmittance. Theopening ratio is the percentage of a translucent portion of each of thefirst electrode pattern 216A and the second electrode pattern 216Bexcluding the metal thin wires. For example, the opening ratio is 90% inthe case of the square grids 224A and 224B having a wire width of 15 μmand a pitch of 300 μm.

[Light Transmissive Part]

The “light transmissive part” in the present embodiment means atranslucent portion other than the first electrode pattern 216A and thesecond electrode pattern 216B, of each of the first conductive sheet212A and the second conductive sheet 212B. As described above, thetransmittance of the light transmissive part is 90% or more, preferably95% or more, further preferably 97% or more, further more preferably 98%or more, and most preferably 99% or more, in terms of the transmittanceindicated by the minimum value of the transmittance in a wavelengthregion of 380 to 780 nm excluding contributions to light absorption andreflection of the first transparent substrate 214A and the secondtransparent substrate 214B.

[First Conductive Sheet 212A and Second Conductive Sheet 212B]

The thickness of each of the first transparent substrate 214A and thesecond transparent substrate 214B in the first conducive sheet 212A andthe second conductive sheet 212B according to the present embodiment ispreferably 5 to 350 μm and further preferably 30 to 150 μm. If thethickness thereof is set within such a range of 5 to 350 μm, a desiredtransmittance of visible light can be obtained, and handling is easy.

The thickness of the metal silver part provided on each of the firsttransparent substrate 214A and the second transparent substrate 214B canbe determined as appropriate in accordance with the applicationthickness of coating for the silver-salt-containing layer applied ontoeach of the first transparent substrate 214A and the second transparentsubstrate 214B. The thickness of the metal silver part can be selectedfrom 0.001 mm to 0.2 mm, and is preferably 30 μm or less, morepreferably 20 μm or less, further preferably 0.01 to 0 μm, and mostpreferably 0.05 to 5 μm. Moreover, it is preferable that the metalsilver part be patterned. The metal silver part may have asingle-layered structure, and may have a multi-layered structure of twoor more layers. In the case where the metal silver part is patterned andhas a multi-layered structure of two or more layers, the metal silverpart can be provided with different color sensitivities so as to bereactive to different wavelengths. As a result, if the metal silver partis exposed to light with different wavelengths, different patterns canbe formed in the respective layers.

For use in a touch panel, a smaller thickness of the conductive metalpart is more preferable, because the viewing angle of a display panel iswider. Also in terms of enhancement in visibility, a reduction inthickness of the conductive metal part is required. From suchperspectives, the thickness of the layer made of the conductive metalsupported by the conductive metal part is preferably less than 9 μm,more preferably 0.1 μm or more and less than 5 μm, and furtherpreferably 0.1 μm or more and less than 3 μm.

In the present embodiment, the metal silver part having a desiredthickness can be formed by controlling the application thickness of thesilver-salt-containing layer, and the thickness of the layer made of theconductive metal grains can be freely controlled by the physicaldevelopment and/or the plating process. Hence, even the first conductivesheet 212A and the second conductive sheet 212B each having a thicknessthat is less than 5 μm and preferably less than 3 μm can be easilyformed.

Note that the method of manufacturing the first conductive sheet 212Aand the second conductive sheet 212B according to the present embodimentdoes not necessarily need to include the plating step and the like. Thisis because the method of manufacturing the first conductive sheet 212Aand the second conductive sheet 212B according to the present embodimentcan obtain a desired surface resistance by adjusting the amount ofapplied silver and the volume ratio of silver/binder of the silver saltemulsion layer. Note that a calendering process and the like may beperformed as needed.

(Hardening Process after Development Process)

It is preferable to perform a hardening process on the silver saltemulsion layer by immersing the same in a hardener after performing thedevelopment process thereon. Examples of the hardener include:dialdehydes such as glutaraldehyde, adipaldehyde, and2,3-dihydroxy-1,4-dioxane; and inorganic compounds such as boric acidand chrome alum/potassium alum, which are described in Japanese PatentApplication Laid-Open No. 2-141279.

Note that the present invention can be used in appropriate combinationwith techniques disclosed in the following Japanese Patent ApplicationLaid-Opens and pamphlets of International Publications in Table 1 andTable 2. Expressions such as “Japanese Patent Application Laid-Open No.”and “Pamphlet of International Publication No. WO” are omitted.

TABLE 1 2004-221564 2004-221565 2007-200922 2006-352073 2007-1292052007-235115 2007-207987 2006-012935 2006-010795 2006-228469 2006-3324592009-21153 2007-226215 2006-261315 2007-072171 2007-102200 2006-2284732006-269795  206-269795 2006-324203 2006-228478 2006-228836 2007-0093262006-336090 2006-336099 2006-348351 2007-270321 2007-270322 2007-2013782007-335729 2007-134439 2007-149760 2007-208133 2007-178915 2007-3343252007-310091 2007-116137 2007-088219 2007-207883 2007-013130 2005-3025082008-218784 2008-227350 2008-227351 2008-244067 2008-267814 2008-2704052008-277675 2008-277676 2008-282840 2008-283029 2008-288305 2008-2884192008-300720 2008-300721 2009-4213 2009-10001 2009-16526 2009-213342009-26933 2008-147507 2008-159770 2008-159771 2008-171568 2008-1983882008-218096 2008-218264 2008-224916 2008-235224 2008-235467 2008-2419872008-251274 2008-251275 2008-252046 2008-277428

TABLE 2 2006/001461 2006/088059 2006/098333 2006/098336 2006/0983382006/098335 2006/098334 2007/001008

Examples

Hereinafter, the present (mention is further specifically described byway of examples of the present invention. Note that materials, usageamounts, percentages, processing contents, processing procedures, andthe like described in the following examples can be changed asappropriate within a range not departing from the gist of the presentinvention. Accordingly, the scope of the present invention should not belimitatively interpreted by way of the following specific examples.

<Level 1>

(Silver Halide Photosensitive Material)

Prepared was an emulsion containing 10.0 g of gelatin for 150 g of Ag inan aqueous medium and containing silver iodobromochloride grains (I=0.2mol %. Br=40 mol %) having a sphere-equivalent diameter of 0.1 μm onaverage.

Moreover. K₃Rh₂Br₉ and K₂IrCl₆ were added to the emulsion at aconcentration of 1×10⁻⁷ (mole/mole silver), and the silver bromidegrains were doped with Rh ions and Ir ions. Na₂PdCl₄ was added to theemulsion, and was further subjected to gold-sulfur sensitization usingchlorauric acid and sodium thiosulfate. Then, together with a gelatinhardener, the emulsion was applied onto the substrate 30 (here,polyethylene terephthalate (PET)) at a silver application amount of 10g/m². At that time, the volume ratio of Ag/gelatin was set to 2/1.

Such application was performed on a PET support having a width of 30 cm,at a width of 25 cm and a length of 20 m. Both the ends of the PETsupport were cut off by 3 cm for each end such that a central part (24cm) of the application was left, whereby a silver halide photosensitivematerial in a rolled state was obtained.

(Exposure to Light)

An exposure pattern for the first electrode pattern 10 was formed suchthat the first electrode pattern 10 had the comb-shaped structureillustrated in FIG. 6, by forming the first conductive patterns 12 andthe sub-nonconduction patterns 18. An exposure pattern for the secondelectrode pattern 40 was formed such that the second electrode pattern40 had the strip-shaped structure illustrated in FIG. 23. The exposureto light was performed through photomasks having such patterns asdescribed above, using parallel light emitted from a light source thatwas a high-pressure mercury lamp.

(Development Process)

-   -   Developing solution IL prescription

hydroquinone 20 g  sodium sulfite 50 g  potassium carbonate 40 g ethylenediaminetetraacetate 2 g potassium bromide 3 g polyethyleneglycol 2000 1 g potassium hydroxide 4 g pH adjusted to 10.3

-   -   Fixing solution IL prescription

ammonium thiosulfate solution (75%) 300 ml ammonium sulfite monohydrate25 g 1,3-diaminopropanetetraacetate 8 g acetate 5 g ammonia water (27%)1 g pH adjusted to 6.2

With the use of the above-mentioned processing solutions, the exposedphotosensitive material was processed by an automatic developing machineFG-710PTS produced by Fujifilm Corporation, under processing conditions:35° C. and 30 seconds for development: 34° C. and 23 seconds for fixing;and flowing water (5 L/min) and 20 seconds for water washing.

B (area of sub-nonconduction pattern)/[A (area of first conductivepattern)+B (area of sub-nonconduction pattern)] was set to 5%. The widthof each metal thin wire was set to 5 μm, and the length of one side ofeach of the grids 26 and 46 was set to 250 μm.

(Levels 2 to 9)

According to the same method as that in Level 1, a plurality ofconductive sheets 1 having different values of B/(A+B) were made. Table3 shows the values of each level.

(Levels 10 to 20)

According to the same method as that in Level 1, a plurality ofconductive sheets 1 having different values of B/(A+B) were made, theconductive sheets 1 each including: the first electrode pattern 10including the first conductive patterns 12 each having the X-shapedstructures; and the second electrode pattern 40 including the secondconductive patterns 42 each having the strip-shaped structure. Table 3shows the values of each level.

TABLE 3 Total Width (Wb) First Total Width (Wa) of Sub- Conductive ofFirst Conductive nonconduction Sensitivity Level No. Pattern ShapeB/(A + B) Pattern Lines Patterns of Finger 1 Comb-Shaped  5% 4.75 0.25 DStructure 2 Comb-Shaped 10% 4.50 0.50 C Structure 3 Comb-Shaped 20% 4.001.00 C Structure 4 Comb-Shaped 40% 3.00 2.00 B Structure 5 Comb-Shaped50% 2.50 2.50 A Structure 6 Comb-Shaped 60% 2.00 3.00 A Structure 7Comb-Shaped 80% 1.00 4.00 C Structure 8 Comb-Shaped 97% 0.15 4.85 DStructure 9 Comb-Shaped  0% 5.00 0.00 D Structure 10 X-Shaped  5% — — DStructures 11 X-Shaped 10% — — C Structures 12 X-Shaped 20% — — BStructures 13 X-Shaped 30% — — A Structures 14 X-Shaped 45% — — AStructures 15 X-Shaped 50% — — A Structures 16 X-Shaped 65% — — CStructures 17 X-Shaped 70% — — C Structures 18 X-Shaped 80% — — CStructures 19 X-Shaped 97% — — D Structures 20 X-Shaped  0% — — DStructures

(Evaluations)

For Levels 1 to 20, when a finger was brought into contact, it wasdetermined whether or not the touch with finger could be sensed. A wasgiven to the case where the touch with finger could be sufficientlysensed. B was given to the case where the contact thereof could besensed with almost no problem. C was given to the case where the contactthereof could not be stably sensed. D was given to the case where thecontact thereof could hardly be sensed.

With regard to the first conductive patterns each having the comb-shapedstructure and the first conductive patterns each having the X-shapedstructures, favorable results were obtained in a range of5%≤B/(A+B)≤97%, and further preferable results were obtained in a rangeof 10%≤B/(A+B)≤80%.

As shown in Table 4, with regard to the first conductive patterns eachhaving the comb-shaped structure in Levels 21 to 25, most preferableresults were obtained in a range of 40%≤B/(A+B)≤60%. With regard to thefirst conductive patterns each having the X-shaped structures, furtherfavorable results were obtained in a range of 30%≤B2/(A2+B2)≤50%, andmost preferable results were obtained in a range of 20%≤B2/(A2+B2)≤50%.

TABLE 4 Total Width (Wb) First Total Width (Wa) of of Sub- ConductiveFirst Conductive nonconduction Sensitivity Level No. Pattern ShapeB/(A + B) Pattern Lines Patterns of Finger 21 Comb-Shaped 50% 1.00 1.00A Structure 22 Comb-Shaped 50% 5.00 5.00 A Structure 23 Comb-Shaped 60%1.00 1.50 A Structure 24 Comb-Shaped 60% 2.50 3.75 A Structure 25Comb-Shaped 60% 3.33 5.00 A Structure

(Evaluations)

With regard to the first conductive patterns each having the comb-shapedstructure in Levels 21 to 25, most preferable results were obtained inthe case of a combination of (1) 1.0 mm≤Wa≤5.0 mm and (2) 1.5 mm≤Wb≤5.0mm, in a range of 50%≤B/(A+B)≤60%.

Next, for laminated conductive sheets according to Levels 26 to 33, thesurface resistance and the transmittance were measured, and moirepatterns and the visibility were evaluated. The details of Levels 26 to33, the measurement results, and the evaluation results are shown inTable 5.

<Levels 26 to 33>

(Silver Halide Photosensitive Material)

Prepared was an emulsion containing 10.0 g of gelatin for 150 g of Ag inan aqueous medium and containing silver iodobromochloride grains (I=0.2mol %, Br=40 mol %) having a sphere-equivalent diameter of 0.1 μm onaverage.

Moreover. K₃Rh₂Br₉ and K₂IrCl₆ were added to the emulsion at aconcentration of 1×10⁻⁷ (mole/mole silver), and the silver bromidegrains were doped with Rh ions and Ir ions. Na₂PdCl₄ was added to theemulsion, and was further subjected to gold-sulfur sensitization usingchlorauric acid and sodium thiosulfate. Then, together with a gelatinhardener, the emulsion was applied onto each of the first transparentsubstrate 214A and the second transparent substrate 214B (here,polyethylene terephthalate (PET)) at a silver application amount of 10g/m². At that time, the volume ratio of Ag/gelatin was set to 2/1.

Such application was performed on a PET support having a width of 30 cm,at a width of 25 cm and a length of 20 m. Both the ends of the PETsupport were cut off by 3 cm for each end such that a central part (24cm) of the application was left whereby a silver halide photosensitivematerial in a rolled state was obtained.

(Exposure to Light)

An exposure pattern for the first conductive sheet 212A was a patternillustrated in FIG. 34 and FIG. 30, and was formed on the firsttransparent substrate 214A having an A4-size (210 mm×297 mm). Anexposure pattern for the second conductive sheet 212B was a patternillustrated in FIG. 34 and FIG. 37, and was formed on the secondtransparent substrate 214B having an A4-size (210 mm×297 mm). Theexposure to light was performed through photomasks having such patternsas described above, using parallel light emitted from a light sourcethat was a high-pressure mercury lamp.

(Development Process)

-   -   Developing solution IL prescription

hydroquinone 20 g  sodium sulfite 50 g  potassium carbonate 40 g ethylenediaminetetraacetate 2 g potassium bromide 3 g polyethyleneglycol 2000 1 g potassium hydroxide 4 g pH adjusted to 10.3

-   -   Fixing solution IL prescription

ammonium thiosulfate solution (75%) 300 ml ammonium sulfite monohydrate25 g 1,3-diaminopropanetetraacetate 8 g acetate 5 g ammonia water (27%)1 g pH adjusted to 6.2

With the use of the above-mentioned processing solutions, the exposedphotosensitive material was processed by the automatic developingmachine FG-71 OPTS produced by Fujifilm Corporation, under processingconditions: 35° C. and 30 seconds for development: 34° C. and 23 secondsfor fixing; and flowing water (5 L/min) and 20 seconds for waterwashing.

(Level 26)

The wire width of each of conducive parts (the first electrode pattern216A and the second electrode pattern 216B) of the made first conductivesheet 212A and the made second conductive sheet 212B was set to 1 μm,and the length of one side of each of the grids 224A and 224B was set to50 μm.

(Level 27)

The first conducts e sheet 212A and the second conductive sheet 212Baccording to Level 27 were made in a manner similar to that in Level 21,except that the wire width of each conductive part was set to 3 μm andthat the length of one side of each of the grids 224A and 224B was setto 100 μm.

(Level 28)

The first conductive sheet 212A and the second conductive sheet 212Baccording to Level 28 were made in a manner similar to that in Level 21,except that the wire width of each conductive part was set to 4 μm andthat the length of one side of each of the grids 224A and 224B was setto 150 μm.

(Level 29)

The first conductive sheet 212A and the second conductive sheet 212Baccording to Level 29 were made in a manner similar to that in Level 21,except that the wire width of each conductive part was set to 5 μm andthat the length of one side of each of the grids 224A and 224B was setto 210 μm.

(Level 30)

The first conductive sheet 212A and the second conductive sheet 212Baccording to Level 30 were made in a manner similar to that in Level 21,except that the wire width of each conductive part was set to 8 μm andthat the length of one side of each of the grids 224A and 224B was setto 250 μm.

(Level 31)

The first conductive sheet 212A and the second conductive sheet 212Baccording to Level 31 were made in a manner similar to that in Level 21,except that the wire width of each conductive part was set to 9 μm andthat the length of one side of each of the grids 224A and 224B was setto 300 μm.

(Level 32)

The first conductive sheet 212A and the second conductive sheet 212Baccording to Level 32 were made in a manner similar to that in Level 21,except that the wire width of each conductive part was set to 10 μm andthat the length of one side of each of the grids 224A and 224B was setto 300 μm.

(Level 33)

The first conductive sheet 212A and the second conductive sheet 212Baccording to Level 33 were made in a manner similar to that in Level 21,except that the wire width of each conductive part was set to 15 μm andthat the length of one side of each of the grids 224A and 224B was setto 400 μm.

(Surface Resistance Measurement)

In order to check whether or not the detection accuracy was sufficient,the surface resistance of each of the first conductive sheet 212A andthe second conductive sheet 212B was obtained as the average value ofvalues that were measured at arbitrary ten points using a four-pointprobe array (ASP). Loresta GP (Model No. MCP-T610) produced by DiaInstruments Co., Ltd.

(Transmittance Measurement)

In order to check whether or not the transparency was sufficient, thetransmittance of each of the first conductive sheet 212A and the secondconductive sheet 212B was measured using a spectrophotometer.

(Moire Pattern Evaluation)

In each of Levels 26 to 33, a laminated conductive sheet was made bylaminating the first conductive sheet 212A on the second conductivesheet 212B. After that, a touch panel was manufactured by attaching thelaminated conductive sheet to a display screen of a liquid crystaldisplay device. After that, the touch panel was set on a spinning disk,and the liquid crystal display device was driven to display a whitecolor. In that state, the spinning disk was spun at a bias angle between−45° and +45°, and moire patterns were visually observed and evaluated.

The moire patterns were evaluated at an observation distance of 1.5 mfrom the display screen of the liquid crystal display device. A wasgiven to the case where the moire patterns were not obviously found. Bwas given to the case where the moire patterns were slightly found in anon-problematic level. C was given to the case where the moire patternswere obviously found.

(Visibility Evaluation)

Prior to the moire pattern evaluation described above, when the touchpanel was set on the spinning disk and when the liquid crystal displaydevice was driven to display a white color, it was checked with nakedeyes whether or not there were thicker lines and black spots and whetheror not the break parts of the first conductive sheet 212A and the secondconductive sheet 212B stood out.

TABLE 5 Wire Width (μm) Length (μm) Surface Moire of Conductive of OneSide Resistance Transmittance Pattern Visibility Level No. Pattern ofGrid (Ω/sq.) (%) Evaluation Evaluation 26 1 50 55 85 A A 27 3 100 55 86A A 28 4 150 50 87 A A 29 5 210 40 88 A A 30 8 250 50 87 A A 31 9 300 4586 A A 32 10 300 40 86 A A 33 15 400 38 85 B B

In this regard, for Levels 26 to 32 of Levels 26 to 33, all of theconductive properties, the transmittance, the moire patterns, and thevisibility were favorable. Although Level 33 was inferior to Levels 26to 32 in the moire pattern evaluation and the visibility evaluation, themoire patterns slightly found in Level 33 were in a non-problematiclevel, and did not hinder observation of an image displayed on thedisplay device.

Moreover, a projected capacitive touch panel was made using thelaminated conductive sheet according to each of Levels 26 to 33. Whenthe projected capacitive touch panel was operated by touching with afinger, it was found out that the response speed was high and that thedetection sensitivity was excellent. Moreover, when the projectedcapacitive touch panel was operated by touching two or more points, itwas confirmed that favorable results could be similarly obtained andthat multi-touch input could be dealt with.

The conductive sheet for the touch panel and the touch panel accordingto the present invention are not limited to the above-mentionedembodiments, and can have various configurations without departing fromthe gist of the present invention, as a matter of course.

What is claimed is:
 1. A conductive sheet for a touch panel, theconductive sheet comprising: a first electrode pattern including: aplurality of first conductive patterns that extend in a first directionand are formed by a plurality of first grids made of a plurality offirst metal thin wires that are arranged in a first single plane andintersect with each other; and a plurality of first nonconductivepatterns that are alternated with the first conductive patterns andelectrically separate the first conductive patterns from each other; anda second electrode pattern including: a plurality of second conductivepatterns that extend in a second direction orthogonal to the firstdirection and are formed by a plurality of second grids made of aplurality of second metal thin wires that are arranged in a secondsingle plane and intersect with each other; and a plurality of secondnonconductive patterns that are alternated with the second conductivepatterns and electrically separate the second conductive patterns fromeach other, wherein: the first conductive patterns include, in one ormore regions enclosed by the first metal thin wires, one or moresub-nonconduction patterns made of a plurality of third metal thin wiresthat are arranged in the first single plane and electrically separatedfrom the first metal thin wires; the second nonconductive patterns areformed by a plurality of third grids made of a plurality of fourth metalthin wires that are arranged in the second single plane, intersect witheach other and are electrically separated from the second metal thinwires; the first conductive patterns and the second conductive patternsare orthogonal to each other in top view; a plurality of intersectionparts of the first metal thin wires are respectively placed in openingregions of the second and third grids such that the first grids and thesecond and third grids form first small grids in top view; and a wirewidth of the first metal thin wires and the second metal thin wires isnot smaller than 1 μm and not larger than 7 μm.
 2. The conductive sheetaccording to claim 1, wherein the first, second and third grids have arhomboid shape.
 3. The conductive sheet according to claim 2, whereinthe first, second and third grids have a same shape with each other. 4.The conductive sheet according to claim 1, wherein the first metal thinwires and the second metal thin wires are made of copper.
 5. Theconductive sheet according to claim 1, wherein: a length of one side ofeach of the first grids is not shorter than 300 μm; and an opening ratioof the first conductive patterns is not smaller than 95%.
 6. Theconductive sheet according to claim 1, wherein the first small gridshave a rhomboid shape.
 7. The conductive sheet according to claim 1,wherein the third metal thin wires in the one or more sub-nonconductionpatterns intersect with each other.
 8. The conductive sheet according toclaim 1, wherein the third metal thin wires in the one or moresub-nonconduction patterns intersect with each other to make a pluralityof fourth grids.
 9. The conductive sheet according to claim 8, wherein aplurality of intersection parts of the third metal thin wires arerespectively placed in opening regions of the second and third gridssuch that the fourth grids and the second and third grids form secondsmall grids in top view.
 10. The conductive sheet according to claim 9,wherein the second small grids have a rhomboid shape.
 11. The conductivesheet according to claim 8, wherein the first, second, third and fourthgrids have a rhomboid shape.
 12. The conductive sheet according to claim11, wherein the first, second, third and fourth grids have a same shapewith each other.
 13. The conductive sheet according to claim 1, whereina wire width of the third and fourth metal thin wires is not smallerthan 1 μm and not larger than 7 μm.
 14. The conductive sheet accordingto claim 13, wherein the first, second, third and fourth metal thinwires are made of copper.
 15. The conductive sheet according to claim 1,wherein the first nonconductive patterns are made of a plurality offifth metal thin wires that are arranged in the first single plane andelectrically separated from the first metal thin wires.
 16. Theconductive sheet according to claim 15, wherein the fifth metal thinwires in the first nonconductive patterns intersect with each other tomake a plurality of fifth grids.
 17. The conductive sheet according toclaim 16, wherein a plurality of intersection parts of the fifth metalthin wires are respectively placed in opening regions of the second andthird grids such that the fifth grids and the second and third gridsform third small grids in top view.
 18. The conductive sheet accordingto claim 17, wherein the third small grids have a rhomboid shape. 19.The conductive sheet according to claim 16, wherein the first, second,third and fifth grids have a rhomboid shape.
 20. The conductive sheetaccording to claim 19, wherein the first, second, third and fifth gridshave a same shape with each other.